#!/usr/bin/perl
# This is a major re-write of the original daemon I wrote, although
# quite a bit of code was re-used where it made sense.
##########################################################################
#                                                                        #
#                       LOCAL CONFIG OPTIONS                             #
#    These have been moved to vanprod.conf.                              #
#    See the embedded documentation, use perldoc, or run pod2man         #
#    as outlined in the README and then read the resulting man page      #
#    for further details about the settings.                             #
#                                                                        #
##########################################################################

=head1 NAME

vanprod - Perl daemon to communicate with a Davis Vantage Pro weather station.

=head1 SYNOPSIS

vanprod [ -c <path/to/vanprod.conf> -dlnt ]

=head1 DESCRIPTION


B<-c /path/to/vanprod.conf>  This allows you to override the location of the configuration file.  Defaults to /etc/vanprod.conf if not present.

B<-d>  Debug mode.  This is intended only for short term diagnosis of problems you may be having.  vanprod will become a daemon, but it will be EXTREMELY chatty in writing information into the syslog at the debug priority.  You may also use this in conjuction with -t for initial testing and debugging.

B<-l>  Calculate loop ratio.  See comments below or in vanprod.conf for details on this value.  The daemon will calculate the loop ratio setting for your system and begin writing a message to syslog at the info level after approximately 24 hours.  The message will repeat approximately every hour.

B<-n>  No database updates.  vanprod will not try to load the DBI module or make any updates to a database.  Text files as described below are not affected by this option.

B<-t>  Test mode.  vanprod will not become a daemon.  It will test for correct communication with the weather station, print the results on stdout and exit.


=head1 vanprod.conf file


B<tty = /dev/ttyS1> This is the serial port where your weather station is connected.

B<facility = local0> This is the syslog facility that the daemon will use for messages.  Make sure that what you put here is configured in your syslog.conf file.

B<directory = /some/path/to/weather>  This is the directory where the daemon will write the output files it generates.  Details on these files and their contents are described below.

B<piddir = /var/run>  This is the directory where the daemon will write a file containing it's pid.  The name of the file is vanprod.pid.

B<num_updates = 12>  This is the number of times per hour to post updates to internet sites.  The default setting is every 5 minutes.  For every 10 minutes set this to 6, for every 15 set it to 4, etc.  If you set this to anything less than 0 or greater than 60 it will revert to the default of 12.  If you do not want to update internet sites at all set this to 0. Currently the daemon supports updates to weather underground and APRSWXNET/CWOP.  Keep in mind that APRSWXNET/CWOP requests that data be sent no more frequently than once per five minutes.

B<send_to_wu = 1>  This defines whether or not to update weather underground.  If this is set to 1 yes or true, vanprod will attempt to send data to weather underground.  Any other value will be interpreted as false. 

B<send_to_cwop = 1>  Same as above, only for APRSWXNET/CWOP.  If you are not familiar with what this is or would like info on signing up, see http://www.wxqa.com

B<wu_id = MY_STATION>  Set this to your station id assigned to you by weather underground.

B<wu_password = mypassword>   Set this to your weather underground password.

B<callsign = CW9999>  Your ham callsign or CWOP ID for APRSWXNET/CWOP.  Use upper case in the value.  I do recommend that you use an elevation of 0 on your Vantage Pro console, especially if you are reporting or plan to report to APRSWXNET/CWOP.  The number they expect to have provided is the altimeter.  The only way to have the Vantage Pro report this is by using 0 for your elevation.  See the section OTHER NOTES AND THOUGHTS for details about this.

B<cwop_password = -1>  Your cwop password if you are a ham operator and have one.  This password allows packets coming from licensed ham operators to be validated and passed on to an RF (amateur packet radio) network by an Igate.  If you are a licensed ham and would like to enable the possibility for your weather data to be broadcast on a local packet radio network, set your passcode here.  To obtain your passcode, you may send your callsign to russell.b.chadwick@noaa.gov, or I will be happy to provide this information for you.  Again, just e-mail your callsign to me at stsander@sblan.net.  Folks using a CW#### ID (i.e. non-hams) should leave this set to -1.

B<cwop0 through cwop3>  This is where you can set the order in which a connection attempt is made to the cwop servers.  You may want to change this order so that server 0 is the closest to your location server 1 is the next closest and so forth.  

B<lat = 1234.56N>
B<lon = 12345.67W>  Your latitude and longitude.  These are used for APRSWXNET/CWOP reports.  The format for latitude is exactly 4 digits followed by a decimal then 2 digits followed by a hemisphere designator.  The digits are ddmm.mm where d is degrees, m is minutes carried out to a resolution of 1/100th (.01) of a minute.  Be sure to insert leading zeros as needed.  The longitude is identical except there are 3 digits required for the degrees, so it becomes dddmm.mm.  This follows the LORAN format if you wish to find more details.  Note that the number of digits required is fixed so leading zeros are required for values less than 10 (or 100).  ACME mapper appears to have the most accurate mapping of these values if you don't happen to have a GPS handy.  If you make a format error (or change the format of the defaults) the daemon will write a warning in your syslog instead of sending to APRSWXNET/CWOP.

B<oldobs = 7>  How many days old a dailyobs file should be to be deleted when a new day is started.  Details on what this file contains are below.  Note that this value will only be used when the daemon is running at midnight and starting a new day as part of it's own internal processes.  If you would like to keep these files forever, you can set this to -1.  The dailyobs file is typically between 70 and 75 KB for a 24 hour period.  


B<db = mysql>  Type of database you want to use to store your daily extremes.  The daemon will store the minimum and maximum values and the time they occurred in the database.  

B<db_name = weather>  The name of the database to use.

B<db_user = stan>  Name of database user that can add records to the database you specified on the previous line.

B<db_password = mypassword> Password for the database user described above.

B<db_table = reports>  Name of database table that contains the values we track and store.  The following commands should set things up for you:

	mysql> CREATE TABLE `reports` (
	`date` DATE NOT NULL ,
	`hi_temp` INT( 3 ) ,
	`hi_temp_time` TIME,
	`lo_temp` INT( 3 ) ,
	`lo_temp_time` TIME,
	`peak_wind` INT( 3 ) ,
	`peak_direct` CHAR( 3 ) ,
	`peak_time` TIME,
	`min_wind_chill` CHAR( 3 ) ,
	`wind_chill_time` TIME,
	`year_rain` DECIMAL( 4, 2 ) ,
	`max_rain_rate` DECIMAL( 4, 2 ) ,
	`max_rain_time` TIME,
	`max_barometer` DECIMAL( 4, 2 ) ,
	`max_press_time` TIME,
	`min_barometer` DECIMAL( 4, 2 ) ,
	`min_press_time` TIME,
	`max_humid` INT( 3 ) ,
	`max_humid_time` TIME,
	`min_humid` INT( 3 ) ,
	`min_humid_time` TIME,
	`max_dew` INT( 3 ) ,
	`max_dew_time` TIME,
	`min_dew` INT( 3 ) ,
	`min_dew_time` TIME,
	`max_heat_index` CHAR( 3 ) ,
	`heat_index_time` TIME,
	`daily_rain` DECIMAL( 4, 2 ) ,
	`max_intemp` INT( 3 ) ,
	`max_intemp_time` TIME ,
	`min_intemp` INT( 3 ) ,
	`min_intemp_time` TIME ,
	`max_inhumid` INT( 3 ) ,
	`max_inhumid_time` TIME,
	`min_inhumid` INT( 3 ) ,
	`min_inhumid_time` TIME,
	`max_indew` INT( 3 ) ,
	`max_indew_time` TIME,
	`min_indew` INT( 3 ) ,
	`min_indew_time` TIME,
	PRIMARY KEY ( `date` )
	);

The routine that uploads this information to the database currently uses an sql insert command, so the ordering of the fields is important.  

B<tid0 through tid7 >  This is where you can set up some meaningful strings for the up to 8 transmitters allowed with the wireless Vantage Pro.  

B<alarm_interval = 300>  This controls how often messages are written to syslog and any actions defined below are taken in the event of an alarm.  This should be expressed in seconds as it will be internally adjusted by the loop ratio.  

B<loop_ratio>  This the ratio of the number of passes through the data gathering loop to 1 second of real time.  This value allows the daemon to more accurately track the values that are time based in some manner.  There isn't much effect on shorter intervals like the average wind direction, but for longer intervals such as the barometer trend or 24 hour rainfall totals, the error introduced can be easily noticed. (OK, so maybe I'm a perfectionist.)

B<*_q>  This is where you can set thresholds for the various "silent" alarms.  These settings are independant of the alarms set on the Vantage Pro console.

B<alarm_action>  This is where you can define a script that vanprod will execute whenever an alarm threshold (silent or console) is crossed.  This is in addition to messages that will be written to your syslog.  Two arguments will be passed to this script, the designator for which value has triggered the alarm, and the current value.  Example: for a low outdoor temperature alarm, the arguments passed would be low_outtemp value.  The "designators" are simply the threshold variables without the _q on the end.  If you have the 15 minute rainfall (flash flood) alarm set on your Vantage Pro console, when this triggers, it will be sent to your script with a designator of ff.  Standard out and Standard error will be captured from this script, and any output that is captured will be written to your syslog.

=cut

my $VERSION = '2.1'; # our version for internet updates
use Getopt::Std;
my %opts = ();
getopts('c:dlnt', \%opts);
use strict;
use Device::Davis 1.1;
use Sys::Syslog qw(:DEFAULT setlogsock);
use POSIX;
use POSIX qw(:errno_h :fcntl_h strftime);
unless($opts{n}){ use DBI;};
use Date::Calc qw(Add_Delta_Days);
use Date::Manip qw(ParseDate UnixDate ParseDateString);
my $tty = "";
my $facility = ""; 
my $name = "vanprod"; # name of the executable for syslog and wu
my $directory = ""; 
my $piddir = ""; 
my $num_updates = 12; 
my $wu_id = ""; 
my $wu_password = ""; 
my $cwop_password = "";
my $oldobs = 0; 
my $db = "";
my $db_name = ""; 
my $db_user = ""; 
my $db_password = "";
my $db_table = ""; 
my %tid = ();
my $alarm_interval = 0;
my $callsign = "";
my $lat = "";
my $lon = "";
my @cwops = ();
my $fd = "";  # File descriptor variable
my $count = 0;  #counter variables
my $bytes = "";
my @data = ();  # Array for responses from weather station
my $bar = "";
my $min_bar = "32.00";
my $min_bar_time = "";
my $max_bar = "28.00";
my $max_bar_time = "";
my $outtemp = "";
my $intemp = "";
my $min_outtemp = "200";
my $min_outtemp_time = "";
my $max_outtemp = "-100";
my $max_outtemp_time = "";
my $min_intemp = "200";
my $min_intemp_time = "";
my $max_intemp = "-100";
my $max_intemp_time = "";
my $windsp = "";
my $max_windsp = "-1";
my $max_windsp_time = "";
my $avgwindsp = "";
my $winddir = "";
my $max_winddir = "";
my @cosine = ();
my @sine = ();
my $sumcos = 0;
my $sumsin = 0;
my $avgwinddir = 0;
my $compdir = "";
my $outhum = "";
my $min_outhum = "101";
my $min_outhum_time = "";
my $max_outhum = "-1";
my $max_outhum_time = "";
my $inhum = "";
my $min_inhum = "101";
my $min_inhum_time = "";
my $max_inhum = "-1";
my $max_inhum_time = "";
my $rate = "0.00";
my $max_rate = "-1";
my $max_rate_time = "";
my $con_rate = "";
my $dayrain = "";
my $monrain = "";
my $yearrain = "";
my $sunrise = "";
my $sunset = "";
my @digits = ();  # Array for making sunrise and sunset look pretty
my $dewpt = "";
my $max_dewpt = "-100";
my $max_dewpt_time = "";
my $min_dewpt = "100";
my $min_dewpt_time = "";
my $indewpt = "";
my $max_indewpt = "-100";
my $max_indewpt_time = "";
my $min_indewpt = "100";
my $min_indewpt_time = "";
my $tempc = ""; # Variable for C temperature for formulas that use it
my $ews = "";   # Variable used in dewpoint calc
my $num1 = "";  # Variable used in dewpoint calc
my $num2 = "";  # Variable used in dewpoint calc
my $chill = 100;
my $min_chill = 100;
my $min_chill_time = "00:00:00";
my $hi = -100;  # Heat Index
my $max_hi = -100;
my $max_hi_time = "00:00:00";
my $new_extreme = 0;
my $pid = ""; # Variable for forking to become daemon
my $time_to_die = 0; # Flag for graceful exit
my $hour = ""; # Variables for time based functions
my $minute = 0;
my $sec = "";
my $prev_minute = -1;
my $update_done = 0;  # flag
my %update_minute = ();
my $index = 0;
my $dateutc = "";  # Current date and time UTC
my $ua = new LWP::UserAgent; # For Weatherunderground
my $internet_gust = 0; # Max gust between wu reports
my $gust = 0; # Max gust between daily obs writes
my $db_update_done = 0; # flag
my $new_day = 0;
my $date = "";
my $line = "";
my $dbh = ""; # Database handle
my $sth = ""; # Database statement handle
my $month = "";
my $day = "";
my $year = "";
my $datestr = "";
my $crc = 0;
my @rainfall = ();
my $rainamt = 0;
my $newrain = 0;
my $prev_dayrain = 0;
my $msbyte = "";
my $lsbyte = "";
my $clock_set = 0;
my $trans_bat = 0;
my $con_bat = 0;
my $con_bat_low = 0; # flag for low battery warning
my $con_bat_min = 4.5;
my $trend = "";
my @bar_vals = ();
my $old_bar = 0;
my $bar_diff = 0;
my $forecasticon = "";
my $forecastrule = "";
my $tid_0_low = 0;
my $tid_1_low = 0;
my $tid_2_low = 0;
my $tid_3_low = 0;
my $tid_4_low = 0;
my $tid_5_low = 0;
my $tid_6_low = 0;
my $tid_7_low = 0;
my $alarm0 = 0;
my $alarm1 = 0;
my $alarm2 = 0;
my $bar_fall_alarm = 0;
my $bar_fall_q = "";
my $bar_rise_alarm = 0;
my $bar_rise_q = "";
my $low_intemp_alarm = 0;
my $low_intemp_q = "";
my $hi_intemp_alarm = 0;
my $hi_intemp_q = "";
my $low_inhum_alarm = 0;
my $low_inhum_q = "";
my $hi_inhum_alarm = 0;
my $hi_inhum_q = "";
my $con_rate_alarm = 0;
my $m15_rain_alarm = 0;
my $rain1_q = "";
my $h24_rain_alarm = 0;
my $rain24_q = "";
my $storm_rain_alarm = 0;
my $storm_q = "";
my $low_outtemp_alarm = 0;
my $low_outtemp_q = "";
my $hi_outtemp_alarm = 0;
my $hi_outtemp_q = "";
my $windsp_alarm = 0;
my $windsp_q = "";
my $avgwindsp_alarm = 0;
my $avgwindsp_q = "";
my $low_outdew_alarm = 0;
my $low_outdew_q = "";
my $hi_outdew_alarm = 0;
my $hi_outdew_q = "";
my $heat_alarm = 0;
my $heat_q = "";
my $chill_alarm = 0;
my $chill_q = "";
my $stormrain = 0;
my $bit = 0;
my $stormstart = 0;
my $stormyear = 0;
my $stormmonth = 0;
my $stormday = 0;
my $inetaddr = "";
my $portaddr = "";
my $proto = "";
my $server = "";
my $rain24 = "0.00";
my $rain1 = "0.00";
my @rainfall24 = ();
my %rain = (
	1 => 0,
	24 => 0
);
my %configs = ();
my $var = "";
my $value = "";
my $send_to_wu = 0;
my $send_to_cwop = 0;
my $epoch = time;
my $now = 0;
my $elapsed = 0;
my $loops = 0;
my $ratio = 1;
my $loop_ratio = 1;
my $alarm_action = "";
my @tmp = ();
initialize();
load_values();
# Open the tty
unless(-r "$tty"){die "You do not have read permission for $tty\n";};
unless(-w "$tty"){die "You do not have write permission for $tty\n";};
$fd = station_open($tty) or die "Cannot open $tty $!\n";

=pod

B<Baud Rates>

The factory default baud rate for the Vantage Pro weather station is 19200.  If you need to use a different setting, you may change it in the Davis module source file, Davis.xs.

=cut

if($opts{t}){
$SIG{ALRM} = \&time_out; # set up timeout trap on serial port IO
test();
exit;
};
# Become a daemon
$pid = fork();
if($pid){ exit; };
if(!defined $pid){ die "Couldn't fork -- $!\n";};
# Disassociate with our controlling terminal and stop being part of our
# previous process group.
POSIX::setsid() or die "Can't start new daemon session:  $!\n";
# If we made it this far, we are now a daemon process
# We should do all our reporting via syslog from now on.
setlogsock("unix");  # talk to our local running syslogd
# Connect up with syslogd, log $name as our process name, along with our pid
openlog("$name", "pid", "$facility");
# Record our pid in a file for ease in signaling.
open(PIDFILE, ">$piddir/$name.pid") or syslog("err", "Exiting can't write pid file $piddir/$name.pid %m") and die;
print PIDFILE $$;
close(PIDFILE);
syslog("info", "$name started.");
while($minute < 60){ # initialize a hash with 60 elemets for WU updates
        $update_minute{$minute} = 0; # flag set to off for each minute
        $minute++;
};
if($num_updates){ # if we should be updating weather underground
	$index = 0;
# Sanity check on variable setting
	if($num_updates > 60 || $num_updates < 0){ $num_updates = 12; };
	until($index == $num_updates){
# Identify which minute(s) during the hour to update
		$minute = (60/$num_updates)*$index;
		$minute = sprintf("%.0f", "$minute");
# Set a flag for that minute in the hash
		$update_minute{$minute} = 1;
		if($opts{d}){syslog("debug", "Internet site updates at $minute past the hour");};
		$index++;
	};
}else{
	if($opts{d}){syslog("debug", "No internet site updates");};
};
until($time_to_die == 1){ # Main loop of the daemon
        $sec = (localtime)[0];
        $minute = (localtime)[1];
        $hour = (localtime)[2];
# update the db unless the option was given to disable it.  The flag will 
# never bet set to 0 if this option is present. Also do new day init.
	if($minute == 0 && $hour == 0 && $db_update_done == 0){ 
		update_db(); 
		$db_update_done = 1;
		};
	if($minute == 1 && $hour == 0){ $db_update_done = 0 unless $opts{n};};
	if($minute == 0 && $hour == 0 && $new_day == 0){ start_day();};
	if($minute == 1 && $hour == 0){ $new_day = 0; };
	if($minute == 0 && $hour == 12 && $clock_set == 0){ set_clock();};
	if($minute == 1 && $hour == 12){ $clock_set = 0;};
	get_data(); # The data collection subroutine
        if($num_updates){ # if we should be updating internet sites
                if($update_minute{$minute} && $sec < 30){ # test the flag for this minute
                        update_internet() unless $update_done;
                        $internet_gust = 0 unless $update_done;  # reset variable for gust between reports
                        $update_done = 1;  # set flag to indicate we're done
                }else{
                        $update_done = 0; # reset flag for next update
                };
        };
};
syslog("info", "Caught sigterm.  Dumping stacks.");
close(DAILY);
open(STACK, ">$directory/cosine_stack");
until($#cosine == -1){
  $value = shift(@cosine);
  print STACK "$value\n";
};
close(STACK);
open(STACK, ">$directory/sine_stack");
until($#sine == -1){
  $value = shift(@sine);
  print STACK "$value\n";
};
close(STACK);
open(STACK, ">$directory/bar_stack");
until($#bar_vals == -1){
  $value = shift(@bar_vals);
  if($value){ print STACK "$value\n"; };
};
close(STACK);
open(STACK, ">$directory/rain1_stack");
until($#rainfall == -1){
  $value = shift(@rainfall);
  print STACK "$value\n";
};
close(STACK);
open(STACK, ">$directory/rain24_stack");
until($#rainfall24 == -1){
  $value = shift(@rainfall24);
  print STACK "$value\n";
};
close(STACK);
syslog("info", "Stacks dumped, exiting.");
closelog();
POSIX::close($fd);
exit;
sub initialize{
if($opts{c}){
   open(CONF, "<$opts{c}") or die "Unable to open $opts{c} $!\n";
}else{
   open(CONF, "</etc/vanprod.conf") or die "Unable to open /etc/vanprod.conf $!\n";
};
until(eof(CONF)){
  $line = <CONF>;
  $line =~ s/#.*//; # ignore comments
  $line =~ s/^\s+//;  # no leading whitespace
  $line =~ s/\s+$//;  # no trailing whitespace
  if($line =~ m/^$/){ next; }; # ignore blank lines and go to next line if nothing left
  chomp($line);  
# extract the variable -> value pairs.  Whitespace before and/or after the = 
# or no whitespace on either side of the = is allowed.
  ($var, $value) = split(/\s*=\s*/, $line, 2); 
  $configs{$var} = $value;
};
close(CONF);
$tty = $configs{tty};
$facility = $configs{facility};
$directory = $configs{directory};
$piddir = $configs{piddir};
$num_updates = $configs{num_updates};
$wu_id = $configs{wu_id};
$wu_password = $configs{wu_password};
$cwop_password = $configs{cwop_password};
$oldobs = $configs{oldobs};
$db = $configs{db};
$db_name = $configs{db_name};
$db_user = $configs{db_user};
$db_password = $configs{db_password};
$db_table = $configs{db_table};
my %tid = ( 
  0 => "$configs{tid0}", 
  1 => "$configs{tid1}",
  2 => "$configs{tid2}",
  3 => "$configs{tid3}",
  4 => "$configs{tid4}",
  5 => "$configs{tid5}",
  6 => "$configs{tid6}",
  7 => "$configs{tid7}"
);
$alarm_interval = $configs{alarm_interval};
$callsign = uc($configs{callsign});
$lat = uc($configs{lat});
$lon = uc($configs{lon});
$send_to_wu = $configs{send_to_wu};
$send_to_cwop = $configs{send_to_cwop};
@cwops = ($configs{cwop0}, $configs{cwop1}, $configs{cwop2}, $configs{cwop3});
$loop_ratio = $configs{loop_ratio};
$bar_fall_q = $configs{bar_fall_q};
$bar_rise_q = $configs{bar_rise_q};
$low_intemp_q = $configs{low_intemp_q};
$hi_intemp_q = $configs{hi_intemp_q};
$low_inhum_q = $configs{low_inhum_q};
$hi_inhum_q = $configs{hi_inhum_q};
$rain1_q = $configs{rain1_q};
$rain24_q = $configs{rain24_q};
$storm_q = $configs{storm_q};
$low_outtemp_q = $configs{low_outtemp_q};
$hi_outtemp_q = $configs{hi_outtemp_q};
$windsp_q = $configs{windsp_q};
$avgwindsp_q = $configs{avgwindsp_q};
$low_outdew_q = $configs{low_outdew_q};
$hi_outdew_q = $configs{hi_outdew_q};
$heat_q = $configs{heat_q};
$chill_q = $configs{chill_q};
$alarm_action = $configs{alarm_action};
$date = strftime "%m.%d.%Y", localtime time;
open(DAILY, ">>$directory/dailyobs.$date") or die "Cannot write to daily obervations file $directory/dailyobs.$date $!\n";
# Trap signals and handle them gracefully
$SIG{INT} = \&sigterm;
$SIG{USR1} = \&load_values;
$SIG{TERM} = \&sigterm;
$SIG{HUP} = \&initialize;
$SIG{CHLD} = 'IGNORE';
$SIG{ALRM} = \&time_out; # set up timeout trap on serial port IO
if($num_updates){ use LWP; use Socket; };
$ua->agent("$name/$VERSION" . $ua->agent);  #for W.U.
$alarm_interval = sprintf("%d", ($alarm_interval / $loop_ratio));
$#cosine = sprintf("%d", (60 / $loop_ratio));
$#sine = sprintf("%d", (60 / $loop_ratio));
$#bar_vals = sprintf("%d", (10799 / $loop_ratio));
$#rainfall = sprintf("%d", (3599 / $loop_ratio));
$#rainfall24 = sprintf("%d", (86399 / $loop_ratio));
}; # end initialize
sub load_values{
chdir($directory);
if($opts{n}){ $db_update_done = 1;}; # disable db updates if option is set
# Load previous extreme values that were stored if any
$date = strftime "%m.%d.%Y", localtime time;
if(-e "$directory/extremes.$date"){
	if($opts{d}){print "Initializing variables with values from $directory/extremes.$date\n"; };
        open(EXTREMES, "<$directory/extremes.$date");
        $line = <EXTREMES>;
        chomp($line);
        @data = split /,/, $line;
        $min_bar = $data[0];
        $min_bar_time = $data[1];
        $max_bar = $data[2];
        $max_bar_time = $data[3];
        $min_outtemp = $data[4];
        $min_outtemp_time = $data[5];
        $max_outtemp = $data[6];
        $max_outtemp_time = $data[7];
        $max_windsp = $data[8];
        $max_winddir = $data[9];
        $max_windsp_time = $data[10];
        $min_outhum = $data[11];
        $min_outhum_time = $data[12];
        $max_outhum = $data[13];
        $max_outhum_time = $data[14];
        $min_dewpt = $data[15];
        $min_dewpt_time = $data[16];
        $max_dewpt = $data[17];
        $max_dewpt_time = $data[18];
        $min_chill = $data[19];
	if($min_chill eq "--"){ $min_chill = 100; };
        $min_chill_time = $data[20];
        $max_hi = $data[21];
	if($max_hi eq "--"){ $max_hi = -100; };
        $max_hi_time = $data[22];
        $max_rate = $data[23];
        $max_rate_time = $data[24];
	$prev_dayrain = sprintf("%.2f", ($data[25] * 100));
	$yearrain = $data[26];
        $min_intemp = $data[27];
        $min_intemp_time = $data[28];
        $max_intemp = $data[29];
        $max_intemp_time = $data[30];
        $min_inhum = $data[31];
        $min_inhum_time = $data[32];
        $max_inhum = $data[33];
        $max_inhum_time = $data[34];
        $min_indewpt = $data[35];
        $min_indewpt_time = $data[36];
        $max_indewpt = $data[37];
        $max_indewpt_time = $data[38];
        close(EXTREMES);
}; # end if
if(-e "$directory/cosine_stack"){
  open(STACK, "<$directory/cosine_stack");
  until(eof(STACK)){
    $line = <STACK>;
    chomp($line);
    shift(@cosine);
    push(@cosine, $line);
  };
  close(STACK);
  $#cosine = sprintf("%d", (60 / $loop_ratio));
  foreach $value (@cosine){ $sumcos += $value; };
  unlink("$directory/cosine_stack");
};
if(-e "$directory/sine_stack"){
  open(STACK, "<$directory/sine_stack");
  until(eof(STACK)){
    $line = <STACK>;
    chomp($line);
    shift(@sine);
    push(@sine, $line);
};
  close(STACK);
  $#sine = sprintf("%d", (60 / $loop_ratio));
  foreach $value (@sine){ $sumsin += $value; };
  unlink("$directory/sine_stack");
};
if(-e "$directory/bar_stack"){
  open(STACK, "<$directory/bar_stack");
  until(eof(STACK)){
    $line = <STACK>;
    chomp($line);
    shift(@bar_vals);
    push(@bar_vals, $line);
  };
  close(STACK);
  $#bar_vals = sprintf("%d", (10799 / $loop_ratio));
  unlink("$directory/bar_stack");
};
if(-e "$directory/rain1_stack"){
  open(STACK, "<$directory/rain1_stack");
  until(eof(STACK)){
    $line = <STACK>;
    chomp($line);
    shift(@rainfall);
    push(@rainfall, $line);
  };
  close(STACK);
  $#rainfall = sprintf("%d", (3599 / $loop_ratio));
  foreach $value (@rainfall){
    if($value){
      $count = 0;
      while($count < $value){ $rain{1}++; $count++;};
    };
  $rate = sprintf("%.2f", ($rain{1} / 100));
  $rain1 = sprintf("%.2f", ($rain{1} / 100));
  };
  unlink("$directory/rain1_stack");
};
if(-e "$directory/rain24_stack"){
  open(STACK, "<$directory/rain24_stack");
  until(eof(STACK)){
    $line = <STACK>;
    chomp($line);
    shift(@rainfall24);
    push(@rainfall24, $line);
  };
  close(STACK);
  $#rainfall24 = sprintf("%d", (86399 / $loop_ratio));
  foreach $value (@rainfall24){
    if($value){
      $count = 0;
      while($count < $value){ $rain{24}++; $count++;};
    };
  $rain24 = sprintf("%.2f", ($rain{24} / 100));
  };
  unlink("$directory/rain24_stack");
};
}; # end load_values

=pod

B<Signals>

B<INT> or B<TERM> will cause the daemon to exit gracefully.

B<HUP> Will cause the daemon to re-read the values from vanprod.conf.

B<USR1> Will cause the daemon to re-read the values from the extremes file.

=cut

sub time_out{
# Cause subroutine to die in response to alarm, which allows jumping back into
# script at line following close of eval block.
if($opts{d}){syslog("debug", "Received SIGALM");};
die "Time out reading serial port.";
};
sub sigterm{   # Set a flag to gracefully exit
$time_to_die = 1;
};
sub test{
print "Weather station should be connected to $tty\n";
$count = 0;
wake_up();
print "Sending TEST\n";
$bytes = put_string($fd, "TEST\n");
if($opts{d}){print "Wrote $bytes bytes to $tty\n"; };
$data[0] = get_char($fd); # \n character
$data[1] = get_char($fd); # \r character
$data[2] = get_char($fd);
$data[3] = get_char($fd);
$data[4] = get_char($fd);
$data[5] = get_char($fd);
$data[6] = get_char($fd); # \n character
$data[7] = get_char($fd); # \r character
if($opts{d}){print "Received @data from $tty\n"; };
my $response = pack("C*", $data[2], $data[3], $data[4], $data[5]);
print "Received $response.  That is a ";
if($response eq 'TEST'){
	print "correct response.\n";
}else{
	print "unexpected or incorrect response.\n";
};
};
sub wake_up{
POSIX::tcflush($fd, TCIOFLUSH);
if($count > 3){ # Connection error condition
	if(-e "$piddir/$name.pid"){  # if we are a daemon
		syslog("err", "Connection error.  Waiting 30 seconds for retry.");
		sleep(30);
		$count = 0; # reset error condition for next series of tries
		wake_up();
	}else{  # we are not a daemon
		die "Connection error.\n";
	};
};
$bytes = put_string($fd, "\n");
if($opts{d}){
	if(-e "$piddir/$name.pid"){  # if we are a daemon
		syslog("debug", "Wrote $bytes bytes to $tty");
	}else{
		print "Wake up wrote $bytes bytes to $tty\n";
	};
};
@data = ();
eval{
alarm(1);  # 1 second timeout
$data[0] = get_char($fd);
$data[1] = get_char($fd);
alarm(0);  # reset timeout
}; # end eval
if($@ =~ /Time out reading serial port/){
	$count++;
	wake_up();
};
if($opts{d}){
	if(-e "$piddir/$name.pid"){  # if we are a daemon
		syslog("debug", "Wake up returned @data"); 
	}else{
		print "Wake up returned @data\n";
	};
};
if($data[0] == 10 && $data[1] == 13){ # Test for valid responses
	POSIX::tcflush($fd, TCIOFLUSH);
	return;
}else{ # Response was not what was expected so try again
	$count++;
	wake_up();
};
};
sub update_internet{  # Update weatherunderground
# This subroutine forks it own process after grabbing the current values of the
# variables expected to change.  This boosts overall performance of the daemon
my $avgwinddir = $avgwinddir;
my $avgwindsp = $avgwindsp;
my $internet_gust = $internet_gust;
my $outhum = $outhum;
my $outtemp = $outtemp;
my $rate = $rate;
my $dayrain = $dayrain;
my @tmp = ();
$tmp[0] = $bar;
my $bar = sprintf("%.2f", $bar);
my $dewpt = $dewpt;
my $rain1 = $rain1;
my $rain24 = $rain24;
my $pid = fork();
if($pid){ return; };
if(!defined $pid){ syslog("notice", "Couldn't fork update_ineternet routine %m");};
if($send_to_wu eq "1" or $send_to_wu =~ /yes/i or $send_to_wu =~ /true/i){
  my $dateutc = strftime "%Y-%m-%d %H:%M:%S", gmtime time;
  my $req = new HTTP::Request GET =>"http://weatherstation.wunderground.com/weatherstation/updateweatherstation.php?action=updateraw&ID=$wu_id&PASSWORD=$wu_password&dateutc=$dateutc&winddir=$avgwinddir&windspeedmph=$avgwindsp&windgustmph=$internet_gust&humidity=$outhum&tempf=$outtemp&rainin=$rate&dailyrainin=$dayrain&baromin=$bar&dewptf=$dewpt&softwaretype=$name-$VERSION";
  my $res = $ua->request($req);
  # Test whether we succeeded
  if ($res->is_success) {
          if($opts{d}){syslog("debug", "Weatherunderground upload successful.");};
  } else {
  # Get content of message returned and log it.
          my $response = $res->content;
          syslog("notice", "Weatherunderground upload failed.  $response");
  };
};
if($lat !~ m/\d\d\d\d\.\d\d[NS]/){ 
  syslog("warn", "You have an error in your latitude entry.  Data not sent to APRSWXNET/CWOP.");
  $send_to_cwop = "no";
};
if($lon !~ m/\d\d\d\d\d\.\d\d[EW]/){
  syslog("warn", "You have an error in your longitude entry.  Data not sent to APRSWXNET/CWOP.");
  $send_to_cwop = "no";
};
if($send_to_cwop eq "1" or $send_to_cwop =~ /yes/i or $send_to_cwop =~ /true/i){
  my @time = gmtime();
  my $min = $time[1];
  my $hour = $time[2];
  my $day = $time[3];
  my $response = "";
  $outtemp = sprintf("%.0f", $outtemp);
  $bar = sprintf("%.0f", ($tmp[0] * 338.6388));  # convert to millibars
  $rain1 = $rain1 * 100;
  $rain24 = $rain24 * 100;
  $dayrain = $dayrain * 100;
  if($outhum == 100) { $outhum = 0; }; # Set outhum to 0 if 100%
  foreach $server (@cwops){
    eval{
      $inetaddr = inet_aton($server) or die "Unable to get address for $server\n";
      $portaddr = sockaddr_in(23,$inetaddr);
      $proto = getprotobyname('tcp');
  # Open socket
      socket(SOCKET, PF_INET, SOCK_STREAM,$proto) or die "Unable to open socket: $!\n";
      connect(SOCKET, $portaddr) or next;
      alarm(10);
      recv(SOCKET, $response, 20, MSG_WAITALL);
      alarm(0);
      unless($response =~ /javAPRSSrvr/){ die "Unexpected response, \'$response\', from $server.  Trying next server.\n"; };
      if($cwop_password > 0){
        print SOCKET "user $callsign pass $cwop_password vers $name-$VERSION\r\n";
        printf SOCKET ('%s>APRS,TCPIP*:', $callsign);
      }else{
        print SOCKET "user $callsign pass -1 vers $name-$VERSION\r\n";
        printf SOCKET ('%s>APRS,TCPXX*:', $callsign);
      };
      printf SOCKET ('@%02d%02d%02dz', $day, $hour, $min);
      printf SOCKET ('%s/%s', $lat, $lon);
      printf SOCKET ('_%03d', $avgwinddir);
      printf SOCKET ('/%03d', $avgwindsp);
      printf SOCKET ('g%03d', $internet_gust);
      printf SOCKET ('t%03d', $outtemp);
      printf SOCKET ('r%03d', $rain1);
      printf SOCKET ('p%03d', $rain24);
      printf SOCKET ('P%03d', $dayrain);
      printf SOCKET ('b%05d', $bar);
      printf SOCKET ('h%02d', $outhum);
      print SOCKET ".lvpd";
      print SOCKET "\r\n";
      close(SOCKET);
    };
    if($@ =~ /^Unable to/){
      syslog("notice", "$@");
      next;
    };
    if($@ =~ /^Unexpected response/){
      syslog("notice", "$@");
      next;
    };
    if($@ =~ /^Time out/){
      syslog("notice", "$server does not seem to be responding.\n");
      next;
    };
    if($pid == 0){ exit;  # exit only if we are a child process else return
    }else{ return; };
  };
  syslog("notice", "Unable to connect with any APRSWXNET/CWOP servers");
  if($pid == 0){ exit;}; # exit only if we are a child process else return
};
if($pid == 0){ exit;}; # exit only if we are a child process else return
};
sub start_day{
# Close out daily observations file, and open new one for current day.
# Delete current obs file from previous day now that we are at or past midnight.
# Also delete dailyobs file from $oldobs days ago.
$datestr = UnixDate($date, "%m.%d.%Y");  #reformat date to match what is on file names.
unlink("$directory/currentobs.$datestr") or syslog("notice", "Cannot remove old current observations file $directory/currentobs.$datestr %m");
unlink("$directory/extremes.$datestr") or syslog("notice", "Cannot remove old extremes file $directory/extremes.$datestr %m");
close(DAILY);
$date = strftime "%m.%d.%Y", localtime time;
open(DAILY, ">$directory/dailyobs.$date") or syslog("notice", "Cannot create daily observations file $directory/dailyobs.$date %m");
# Remove dailyobs file from $oldobs days ago
unless($oldobs == -1){
  ($year, $month, $day) = Add_Delta_Days(((localtime)[5] + 1900), ((localtime)[4] + 1), (localtime)[3], -$oldobs);
  $date = ParseDate("$year $month $day");
  $datestr = UnixDate($date, "%m.%d.%Y");
  unlink("$directory/dailyobs.$datestr") or syslog("notice", "Cannot remove old daily observations file $directory/dailyobs.$datestr %m");
};
# Reset date variable to today 
$date = strftime "%m.%d.%Y", localtime time;
# Reset min and max values so current values next loop will be our starting
# point
$min_bar = 32.00;
$max_bar = 28.00;
$min_outtemp = 200;
$max_outtemp = -100;
$max_windsp = -1;
$min_outhum = 101;
$max_outhum = -1;
$min_dewpt = 200;
$max_dewpt = -100;
$min_chill = 100;
$min_chill_time = "00:00:00";
$max_hi = -100;
$max_hi_time = "00:00:00";
$max_rate = -1;
$min_intemp = 200;
$max_intemp = -100;
$min_inhum = 101;
$max_inhum = -1;
$min_indewpt = 200;
$max_indewpt = -100;
# set flag 
$new_day = 1;
if($opts{d}){syslog("debug", "Initialized new day");};
};
sub set_clock{
# I had originally included this as part of the new day routine, then I discovered
# that the act of setting the time at midnight apparently interfered with the station
# console beginning a new day correctly.
# syncronize weather station time with computer's time
wake_up();
$sec = (localtime)[0];
$minute = (localtime)[1];
$hour = (localtime)[2];
$year = (localtime)[5];
$month = ((localtime)[4] + 1);
$day = (localtime)[3];
# Calculate the crc
$crc = crc_accum($crc, $sec);
$crc = crc_accum($crc, $minute);
$crc = crc_accum($crc, $hour);
$crc = crc_accum($crc, $day);
$crc = crc_accum($crc, $month);
$crc = crc_accum($crc, $year);
$msbyte = $crc >> 8;
$lsbyte = $crc << 24;
$lsbyte = $lsbyte >> 24;
$bytes = put_string($fd, "SETTIME\n");
if($opts{d}){ syslog("debug", "Wrote $bytes bytes to $tty for SETTIME"); };
@data = ();
eval{
alarm(1);  # 1 second timeout
$data[0] = get_char($fd);
alarm(0);  # reset timeout
}; # end eval
if($@ =~ /Time out reading serial port/){
        syslog("notice", "Serial port timeout waiting for ack to SETTIME command.");
};
if($data[0] == 6){
        $bytes = 0;
        $bytes += put_unsigned($fd, $sec);
        $bytes += put_unsigned($fd, $minute);
        $bytes += put_unsigned($fd, $hour);
        $bytes += put_unsigned($fd, $day);
        $bytes += put_unsigned($fd, $month);
        $bytes += put_unsigned($fd, $year);
        $bytes += put_unsigned($fd, $msbyte);
        $bytes += put_unsigned($fd, $lsbyte);
        $bytes += put_string($fd, "\n");
        if($opts{d}){ syslog("debug", "Wrote $bytes bytes to $tty for time values"); };
        @data = ();
        eval{
        alarm(1);  # 1 second timeout
        $data[0] = get_char($fd);
        alarm(0);  # reset timeout
        }; # end eval
        if($@ =~ /Time out reading serial port/){
                syslog("notice", "Serial port timeout waiting for ack to SETTIME values.");
        };
        if($data[0] == 6){
                syslog("info", "Weather station time sync'd with system time.");
        }else{
                syslog("notice", "Unable to sync weather station time with system.  Received a response of $data[0] from station.");
        };
}else{
        syslog("notice", "Unable to attempt time sync.  No ack to SETTIME command received from station.");
};
$clock_set = 1;  # set this flag so we only make 1 attempt per 24 hours.  
};
sub update_db{   # update mysql database
# this subroutine will fork into a child process after grabbing the values
# of the variables that are expected to change.  
my $min_outtemp = $min_outtemp;
my $min_outtemp_time = $min_outtemp_time;
my $max_outtemp = $max_outtemp;
my $max_outtemp_time = $max_outtemp_time;
my $min_dewpt = $min_dewpt;
my $max_dewpt = $max_dewpt;
my $min_chill = $min_chill;
if($min_chill == 100){ $min_chill = "--"; };
my $max_hi = $max_hi;
if($max_hi == -100){ $max_hi = "--"; };
my $max_windsp = $max_windsp;
my $max_winddir = $max_winddir;
my $max_windsp_time = $max_windsp_time;
my $min_chill_time = $min_chill_time;
my $yearrain = $yearrain;
my $max_rate = $max_rate;
my $max_rate_time = $max_rate_time;
my $max_bar = sprintf("%.2f", $max_bar);
my $max_bar_time = $max_bar_time;
my $min_bar = sprintf("%.2f", $min_bar);
my $min_bar_time = $min_bar_time;
my $max_outhum = $max_outhum;
my $max_outhum_time = $max_outhum_time;
my $min_outhum = $min_outhum;
my $min_outhum_time = $min_outhum_time;
my $max_dewpt_time = $max_dewpt_time;
my $min_dewpt_time = $min_dewpt_time;
my $max_hi_time = $max_hi_time;
my $dayrain = $dayrain;
my $min_intemp = $min_intemp;
my $min_intemp_time = $min_intemp_time;
my $max_intemp = $max_intemp;
my $max_intemp_time = $max_intemp_time;
my $min_indewpt = $min_indewpt;
my $max_indewpt = $max_indewpt;
my $max_inhum = $max_inhum;
my $max_inhum_time = $max_inhum_time;
my $min_inhum = $min_inhum;
my $min_inhum_time = $min_inhum_time;
my $max_indewpt_time = $max_indewpt_time;
my $min_indewpt_time = $min_indewpt_time;
my $pid = fork();
if($pid){ return; };
if(!defined $pid){ syslog("notice", "Couldn't fork update_db routine %m");};
# get yesterdays date and format it for the database
($year, $month, $day) = Add_Delta_Days(((localtime)[5] + 1900), ((localtime)[4] + 1), (localtime)[3], -1);
my $date = ParseDate("$year $month $day");
my $datestr = UnixDate($date, "%Y-%m-%d");
# round values to nearest integer
$min_outtemp = sprintf("%.0f", $min_outtemp);
$max_outtemp = sprintf("%.0f", $max_outtemp);
$min_dewpt = sprintf("%.0f", $min_dewpt);
$max_dewpt = sprintf("%.0f", $max_dewpt);
$min_intemp = sprintf("%.0f", $min_intemp);
$max_intemp = sprintf("%.0f", $max_intemp);
$min_indewpt = sprintf("%.0f", $min_indewpt);
$max_indewpt = sprintf("%.0f", $max_indewpt);
$min_chill = sprintf("%.0f", $min_chill) unless($min_chill eq "--");
$max_hi = sprintf("%.0f", $max_hi) unless($max_hi eq "--");
eval{
$dbh = DBI->connect("DBI:$db:$db_name","$db_user","$db_password",{
        PrintError => 0,
        RaiseError => 1});
# prepare variables for database entry
$datestr = $dbh->quote($datestr);
$max_outtemp = $dbh->quote($max_outtemp);
$max_outtemp_time = $dbh->quote($max_outtemp_time);
$min_outtemp = $dbh->quote($min_outtemp);
$min_outtemp_time = $dbh->quote($min_outtemp_time);
$max_windsp = $dbh->quote($max_windsp);
$max_winddir = $dbh->quote($max_winddir);
$max_windsp_time = $dbh->quote($max_windsp_time);
$min_chill = $dbh->quote($min_chill);
$min_chill_time = $dbh->quote($min_chill_time);
$yearrain = $dbh->quote($yearrain);
$max_rate = $dbh->quote($max_rate);
$max_rate_time = $dbh->quote($max_rate_time);
$max_bar = $dbh->quote($max_bar);
$max_bar_time = $dbh->quote($max_bar_time);
$min_bar = $dbh->quote($min_bar);
$min_bar_time = $dbh->quote($min_bar_time);
$max_outhum = $dbh->quote($max_outhum);
$max_outhum_time = $dbh->quote($max_outhum_time);
$min_outhum = $dbh->quote($min_outhum);
$min_outhum_time = $dbh->quote($min_outhum_time);
$max_dewpt = $dbh->quote($max_dewpt);
$max_dewpt_time = $dbh->quote($max_dewpt_time);
$min_dewpt = $dbh->quote($min_dewpt);
$min_dewpt_time = $dbh->quote($min_dewpt_time);
$max_hi = $dbh->quote($max_hi);
$max_hi_time = $dbh->quote($max_hi_time);
$dayrain = $dbh->quote($dayrain);
$max_intemp = $dbh->quote($max_intemp);
$max_intemp_time = $dbh->quote($max_intemp_time);
$min_intemp = $dbh->quote($min_intemp);
$min_intemp_time = $dbh->quote($min_intemp_time);
$max_inhum = $dbh->quote($max_inhum);
$max_inhum_time = $dbh->quote($max_inhum_time);
$min_inhum = $dbh->quote($min_inhum);
$min_inhum_time = $dbh->quote($min_inhum_time);
$max_indewpt = $dbh->quote($max_indewpt);
$max_indewpt_time = $dbh->quote($max_indewpt_time);
$min_indewpt = $dbh->quote($min_indewpt);
$min_indewpt_time = $dbh->quote($min_indewpt_time);
$sth = $dbh->prepare("insert into $db_table values ($datestr,$max_outtemp,$max_outtemp_time,$min_outtemp,$min_outtemp_time,$max_windsp,$max_winddir,$max_windsp_time,$min_chill,$min_chill_time,$yearrain,$max_rate,$max_rate_time,$max_bar,$max_bar_time,$min_bar,$min_bar_time,$max_outhum,$max_outhum_time,$min_outhum,$min_outhum_time,$max_dewpt,$max_dewpt_time,$min_dewpt,$min_dewpt_time,$max_hi,$max_hi_time,$dayrain,$max_intemp,$max_intemp_time,$min_intemp,$min_intemp_time,$max_inhum,$max_inhum_time,$min_inhum,$min_inhum_time,$max_indewpt,$max_indewpt_time,$min_indewpt,$min_indewpt_time)");
$sth->execute;
$sth->finish();
$dbh->disconnect;
};  #end of eval
# log error if we caught one
if($@){ 
	syslog("notice", "Database error:  $@"); 
	if($pid == 0){ exit 2;};
}else{
	if($opts{d}){syslog("debug", "Updated $db database.");};
	if($pid == 0){exit;}; # exit only if we are a child process else return
};
if($min_chill eq "--"){ $min_chill = 100; };
if($max_hi eq "--"){ $max_hi = -100; };
};
sub get_data {
if($opts{l}){
  $loops++;
  if(($loops % 3600) == 0 && $loops > 86399){
     $now = time;
     $elapsed = $now - $epoch;
     $ratio = $elapsed / $loops;
     $ratio = sprintf("%.3f", $ratio);
     syslog("info", "Your calculated loop ratio is $ratio."); 
  };
};
$count = 0;
wake_up();
$bytes = put_string($fd, "LOOP 1\n");
if($opts{d}){syslog("debug", "Wrote $bytes bytes to $tty requesting loop packet"); };
$index = 0; # Byte counter
$crc = 0; 
eval{
alarm(1); # Set timeout timer
while($index < 100){
        $data[$index] = get_char($fd);
	if($index){$crc = crc_accum($crc, $data[$index]);};
        $data[$index] = sprintf("%02x", "$data[$index]"); # Convert to hex
        $index++;
};
alarm(0); # Cancel timeout timer
}; #  End of eval
if($@ =~ /Time out reading serial port/){
         syslog("notice", "Serial port time out.  Leaving get_data subroutine.");
         return;
};
if($opts{d}){syslog("debug", "Received LOOP packet.");};
if($crc){
	syslog("notice", "Loop packet failed crc check.");
	POSIX::tcflush($fd, TCIOFLUSH);
	return;
};
# Translate values returned by loop command and store extreme values
$value = hex("$data[9]$data[8]");
if($value < 26000 || $value > 32000){
	syslog("notice", "Barometer value out of range."); 
}else{
  $bar = sprintf("%.3f", ($value / 1000));
  if($bar < $min_bar){
        $min_bar = $bar;
        $min_bar_time = strftime "%H:%M:%S", localtime time;
	$new_extreme = 1;
  };
  if($bar > $max_bar){
        $max_bar = $bar;
        $max_bar_time = strftime "%H:%M:%S", localtime time;
	$new_extreme = 1;
  };
# Calculate the barometer change rate.
# The overall trend is provided by Rev. B formware, but I need to 
# know the rate of change to make the silent alarms work
  push(@bar_vals, $bar); # Place current value on top of stack
  $old_bar = shift(@bar_vals); # Read bottom value from stack
  if(!defined $old_bar){$old_bar = $bar; };
  $bar_diff = $bar - $old_bar;
  if($bar_diff <= -.06){ $trend = "FR"; };
  if($bar_diff > -.06 && $bar_diff <= -.03){ $trend = "FS"; };
  if($bar_diff > -.029 && $bar_diff < .029){ $trend = "ST"; };
  if($bar_diff >= .03 && $bar_diff < .06){ $trend = "RS"; };
  if($bar_diff >=.06){ $trend = "RR"; };
};
$value = hex("$data[11]$data[10]");
if($value < 320 || $value > 1400){
	syslog("notice", "Indoor temperature out of range.");
}else{
  $intemp = sprintf("%.1f", ($value / 10));
  if($intemp < $min_intemp){
	$min_intemp = $intemp;
	$min_intemp_time = strftime "%H:%M:%S", localtime time;
	$new_extreme = 1;
  };
  if($intemp > $max_intemp){
	$max_intemp = $intemp;
	$max_intemp_time = strftime "%H:%M:%S", localtime time;
	$new_extreme = 1;
  };
};
$value = hex("$data[12]");
if($value > 100){ 
	syslog("notice", "Indoor humidity out of range.");
}else{
$inhum = $value;
  if($inhum < $min_inhum){
        $min_inhum = $inhum;
        $min_inhum_time = strftime "%H:%M:%S", localtime time;
        $new_extreme = 1;
  };
  if($inhum > $max_inhum){
        $max_inhum = $inhum;
        $max_inhum_time = strftime "%H:%M:%S", localtime time;
        $new_extreme = 1;
  };
};
$value = hex("$data[14]$data[13]");
# Thanks to Douglas Weaver for finding this bug and providing the fix.
# if $outtemp's top bit is set, then it is really negative 
# (hex() doesn't appear to sign extend).  Need to turn $outtemp to a negative
if($value & 0x8000){ $value -= 0x10000; };
if($value < -400 || $value > 1500){ 
	syslog("notice", "Outdoor temperature out of range."); 
}else{
  $outtemp = sprintf("%.1f", ($value / 10));
  if($outtemp < $min_outtemp){
        $min_outtemp = $outtemp;
        $min_outtemp_time = strftime "%H:%M:%S", localtime time;
	$new_extreme = 1;
  };
  if($outtemp > $max_outtemp){
        $max_outtemp = $outtemp;
        $max_outtemp_time = strftime "%H:%M:%S", localtime time;
	$new_extreme = 1;
  };
};
$value = hex("$data[15]");
if($value > 150){
	syslog("notice", "Wind speed out of range."); 
}else{
  $windsp = $value;
  if($windsp > $gust){ $gust = $windsp; };
  if($windsp > $internet_gust){ $internet_gust = $windsp; };
};
$avgwindsp = hex("$data[16]") unless(hex("$data[16]") > 150);
$value = hex("$data[18]$data[17]");
if($value > 359){
  syslog("notice", "Wind direction out of range.");
}else{
# compute the average wind direction for the previous 3 minutes
  $winddir = $value;
  $sumsin -=  shift(@sine);
  $sumcos -= shift(@cosine); 
  push(@cosine, cos(.01745329 * $winddir));
  push(@sine, sin(.01745329 * $winddir));
  $sumsin += sin(.01745329 * $winddir);
  $sumcos += cos(.01745329 * $winddir);
  $avgwinddir = 57.29578 * atan2($sumsin, $sumcos);
  if($avgwinddir < 0){$avgwinddir += 360; }; 
  $avgwinddir = sprintf("%.0f", $avgwinddir);
# convert degrees to 16 point compass rose directions
  if($winddir < 12){$compdir = "N"};
  if($winddir > 11 && $winddir < 35){$compdir = "NNE"};
  if($winddir > 34 && $winddir < 57){$compdir = "NE"};
  if($winddir > 56 && $winddir < 79){$compdir = "ENE"};
  if($winddir > 78 && $winddir < 102){$compdir = "E"};
  if($winddir > 101 && $winddir < 124){$compdir = "ESE"};
  if($winddir > 123 && $winddir < 147){$compdir = "SE"};
  if($winddir > 146 && $winddir < 169){$compdir = "SSE"};
  if($winddir > 168 && $winddir < 192){$compdir = "S"};
  if($winddir > 191 && $winddir < 214){$compdir = "SSW"};
  if($winddir > 213 && $winddir < 237){$compdir = "SW"};
  if($winddir > 236 && $winddir < 259){$compdir = "WSW"};
  if($winddir > 258 && $winddir < 282){$compdir = "W"};
  if($winddir > 281 && $winddir < 304){$compdir = "WNW"};
  if($winddir > 303 && $winddir < 327){$compdir = "NW"};
  if($winddir > 326 && $winddir < 349){$compdir = "NNW"};
  if($winddir > 348){$compdir = "N"};
  if($windsp > $max_windsp && $windsp < 151){
        $max_windsp = $windsp;
        $max_windsp_time = strftime "%H:%M:%S", localtime time;
        $max_winddir = $compdir;
	$new_extreme = 1;
  };
};
$value = hex("$data[34]");
if($value > 100){ 
	syslog("notice", "Outdoor humidity out of range.");
}else{
  $outhum = $value;
  if($outhum < $min_outhum){
        $min_outhum = $outhum;
        $min_outhum_time = strftime "%H:%M:%S", localtime time;
	$new_extreme = 1;
  };
  if($outhum > $max_outhum){
        $max_outhum = $outhum;
        $max_outhum_time = strftime "%H:%M:%S", localtime time;
	$new_extreme = 1;
  };
};
$stormrain = hex("$data[48]$data[47]");
$stormrain = sprintf("%.2f", ($stormrain / 100));
$stormmonth = 0;
$stormday = 0;
$stormyear = 2000;
if((hex("$data[50]")) < 255 && (hex("$data[49]")) < 255){
  $bit = hex("$data[50]");
  if($bit & 128){ $stormmonth = $stormmonth + 8; };
  if($bit & 64){ $stormmonth = $stormmonth + 4; };
  if($bit & 32){ $stormmonth = $stormmonth + 2; };
  if($bit & 16){ $stormmonth = $stormmonth + 1; };
  if($bit & 8){ $stormday = $stormday + 16; };
  if($bit & 4){ $stormday = $stormday + 8; };
  if($bit & 2){ $stormday = $stormday + 4; };
  if($bit & 1){ $stormday = $stormday + 2; };
  $bit = hex("$data[49]");
  if($bit & 128){ $stormday = $stormday + 1; };
  $stormyear += $bit & 64;
  $stormyear += $bit & 32;
  $stormyear += $bit & 16;
  $stormyear += $bit & 8;
  $stormyear += $bit & 4;
  $stormyear += $bit & 2;
  $stormyear += $bit & 1;
  $stormstart = sprintf("%02d/%02d/%4d", $stormmonth, $stormday, $stormyear);
}else{
  $stormstart = "00/00/00";
};
$dayrain = hex("$data[52]$data[51]");
if($hour == 0 && $minute == 0 && $sec < 4){ $dayrain = 0; };
$con_rate = sprintf("%.2f", (hex("$data[43]$data[42]") / 100));
# I want to calculate my own rain rate.  Folks outside of the climate of the
# US desert Southwest may wonder why, but folks who live in similar climates
# will understand.  
# total the dayrain for the last 3600/$loop_ratio passes through the loop
# and then subtract the oldest value from this to get the amount of
# rainfall in approximately the past hour.
$newrain = $dayrain - $prev_dayrain;
$prev_dayrain = $dayrain;
if($newrain < 0){ 
	$newrain = 0; 
	if($dayrain > 0){ $newrain = $dayrain; };
};
# I discovered that the daemon became a bit of a CPU hog while iterating over
# the rainfall arrays to find the total amount of rainfall for the specific 
# time period.  So, I instead decided to use a value in a hash and increment
# or decrement it as necessary when the totals should change.  
push(@rainfall, $newrain);
push(@rainfall24, $newrain);
if($newrain){
  $count = 0;
  while($count < $newrain){$rain{1}++; $rain{24}++; $count++;};
  $rate = sprintf("%.2f", ($rain{1} / 100));
  $rain1 = sprintf("%.2f", ($rain{1} / 100));
  $rain24 = sprintf("%.2f", ($rain{24} / 100));
  $new_extreme = 1;
};
$value = shift(@rainfall24);
if($value){
  $count = 0;
  while($count < $value){ $rain{24}--; $count++;};
  $rain24 = sprintf("%.2f", ($rain{24} / 100));
  $new_extreme = 1;
};
$value = shift(@rainfall);
if($value){
  $count = 0;
  while($count < $value){ $rain{1}--; $count++;};
  $rate = sprintf("%.2f", ($rain{1} / 100));
  $rain1 = sprintf("%.2f", ($rain{1} / 100));
  $new_extreme = 1;
};
$dayrain = sprintf("%.2f", ($dayrain / 100));
if($rate > $dayrain){ $rate = $dayrain; };
if($hour == 0){ $rate = $dayrain; };
if($rate > $max_rate){
        $max_rate = $rate;
        $max_rate_time = strftime "%H:%M:%S", localtime time;
        $new_extreme = 1;
};
$monrain = hex("$data[54]$data[53]");
$monrain = sprintf("%.2f", ($monrain / 100));
$yearrain = hex("$data[56]$data[55]");
$yearrain = sprintf("%.2f", ($yearrain / 100));
# For the alarm bits, I increment a flag and take action (initally just writing to syslog)
# based on the value of the flag.  This way action is not taken every time through the
# loop but rather at an interval controlled by the user.  Hopefully this approach allows sufficient
# flexability for future enhancements (i.e. doing something besides putting a message
# in the syslog and defining "silent" alarms)
# This action now can call a user specified script and pass 2 arguments.
$alarm0 = hex("$data[71]");
$alarm1 = hex("$data[72]");
$alarm2 = hex("$data[73]");
# The station does not sleep if there is a console alarm.
# So, we will sleep in order to keep the loop timing consistent
if($alarm0 > 0 || $alarm1 > 0 || $alarm2 > 0){ sleep(1); };
if($alarm0 & 1 || $bar_diff <= $bar_fall_q){$bar_fall_alarm++; }else{$bar_fall_alarm = 0; };
if($alarm0 & 2 || $bar_diff >= $bar_rise_q){$bar_rise_alarm++; }else{$bar_rise_alarm = 0; };
if($alarm0 & 4 || $intemp <= $low_intemp_q){$low_intemp_alarm++; }else{$low_intemp_alarm = 0; };
if($alarm0 & 8 || $intemp >= $hi_intemp_q){$hi_intemp_alarm++; }else{$hi_intemp_alarm = 0; };
if($alarm0 & 16 || $inhum <= $low_inhum_q){$low_inhum_alarm++;}else{$low_inhum_alarm = 0; };
if($alarm0 & 32 || $inhum >= $hi_inhum_q){$hi_inhum_alarm++;}else{$hi_inhum_alarm = 0; };
# bit 6 is the alarm clock (aka time alarm) on the console I'm ignoring it here
# bit 7 is not used
if($alarm1 & 1 || $rain1 >= $rain1_q){$con_rate_alarm++; }else{$con_rate_alarm = 0; };
if($alarm1 & 2){$m15_rain_alarm++; }else{$m15_rain_alarm = 0; };
if($alarm1 & 4 || $rain24 >= $rain24_q){$h24_rain_alarm++; }else{$h24_rain_alarm = 0; };
if($alarm1 & 8 || $stormrain >= $storm_q){$storm_rain_alarm++; }else{$storm_rain_alarm = 0; };
# bit 4 is the daily ET alarm I'm ignoring it
# bits 5 - 7 are not used
if($alarm2 & 1 || $outtemp <= $low_outtemp_q){$low_outtemp_alarm++; }else{$low_outtemp_alarm = 0; };
if($alarm2 & 2 || $outtemp >= $hi_outtemp_q){$hi_outtemp_alarm++; }else{$hi_outtemp_alarm = 0; };
if($alarm2 & 4 || $windsp >= $windsp_q){$windsp_alarm++; }else{$windsp_alarm = 0; };
if($alarm2 & 8 || $avgwindsp >= $avgwindsp_q){$avgwindsp_alarm++; }else{$avgwindsp_alarm = 0; };
if($alarm2 & 16 || $dewpt <= $low_outdew_q){$low_outdew_alarm++; }else{$low_outdew_alarm = 0; };
if($alarm2 & 32 || $dewpt >= $hi_outdew_q){$hi_outdew_alarm++; }else{$hi_outdew_alarm = 0; };
if($alarm2 & 64 || $hi >= $heat_q){$heat_alarm++; }else{$heat_alarm = 0; };
if($alarm2 & 128 || $chill <= $chill_q){$chill_alarm++; }else{$chill_alarm = 0; };
if($bar_fall_alarm == 1){
  syslog("warning", "Falling barometer alarm.");
  if($alarm_action ne ""){send_alarm("bar_fall", $bar_diff);};
};
if($bar_fall_alarm > 0 && ($bar_fall_alarm % $alarm_interval) == 0){
  syslog("warning", "Falling barometer alarm.");
  if($alarm_action ne ""){send_alarm("bar_fall", $bar_diff);};
};
if($bar_rise_alarm == 1){
  syslog("warning", "Rising barometer alarm."); 
   if($alarm_action ne ""){send_alarm("bar_rise", $bar_diff);}; 
};
if($bar_rise_alarm > 0 && ($bar_rise_alarm % $alarm_interval) == 0){
    syslog("warning", "Rising barometer alarm.");
     if($alarm_action ne ""){send_alarm("bar_rise", $bar_diff);};
};
if($low_intemp_alarm == 1){
  syslog("warning", "Low indoor temperature alarm."); 
  if($alarm_action ne ""){send_alarm("low_intemp", $intemp);};
};
if($low_intemp_alarm > 0 && ($low_intemp_alarm % $alarm_interval) == 0){
    syslog("warning", "Low indoor temperature alarm.");
    if($alarm_action ne ""){send_alarm("low_intemp", $intemp);};
};
if($hi_intemp_alarm == 1){
  syslog("warning", "High indoor temperature alarm."); 
  if($alarm_action ne ""){send_alarm("hi_intemp", $intemp);};
};
if($hi_intemp_alarm > 0 && ($hi_intemp_alarm % $alarm_interval) == 0){
  syslog("warning", "High indoor temperature alarm."); 
  if($alarm_action ne ""){send_alarm("hi_intemp", $intemp);};
};
if($low_inhum_alarm == 1){
  syslog("warning", "Low indoor humidity alarm."); 
  if($alarm_action ne ""){send_alarm("low_inhum", $inhum);};
};
if($low_inhum_alarm > 0 && ($low_inhum_alarm % $alarm_interval) == 0){
  syslog("warning", "Low indoor humidity alarm."); 
  if($alarm_action ne ""){send_alarm("low_inhum", $inhum);};
};
if($hi_inhum_alarm == 1){
  syslog("warning", "High indoor humudity alarm."); 
  if($alarm_action ne ""){send_alarm("hi_inhum", $inhum);};
  };
if($hi_inhum_alarm > 0 && ($hi_inhum_alarm % $alarm_interval) == 0){
  syslog("warning", "High indoor humudity alarm."); 
  if($alarm_action ne ""){send_alarm("hi_inhum", $inhum);};
};
if($con_rate_alarm == 1){
  syslog("warning", "High rain rate alarm."); 
  if($alarm_action ne ""){send_alarm("rain1", $rain1);};
};
if($con_rate_alarm > 0 && ($con_rate_alarm % $alarm_interval) == 0){
  syslog("warning", "High rain rate alarm."); 
  if($alarm_action ne ""){send_alarm("rain1", $rain1);};
  };
if($m15_rain_alarm == 1){
  syslog("warning", "15 minute rain (flash flood) alarm."); 
  if($alarm_action ne ""){send_alarm("ff", $rain1);};
};
if($m15_rain_alarm > 0 && ($m15_rain_alarm % $alarm_interval) == 0){
  syslog("warning", "15 minute rain (flash flood) alarm."); 
  if($alarm_action ne ""){send_alarm("ff", $rain1);};
};
if($h24_rain_alarm == 1){
  syslog("warning", "24 hour rain total alarm."); 
  if($alarm_action ne ""){send_alarm("rain24", $rain24);};
};
if($h24_rain_alarm > 0 && ($h24_rain_alarm % $alarm_interval) == 0){
  syslog("warning", "24 hour rain total alarm."); 
  if($alarm_action ne ""){send_alarm("rain24", $rain24);};
};
if($storm_rain_alarm == 1){
  syslog("warning", "Storm rain total alarm."); 
  if($alarm_action ne ""){send_alarm("storm", $stormrain);};
};
if($storm_rain_alarm > 0 && ($storm_rain_alarm % $alarm_interval) == 0){
  syslog("warning", "Storm rain total alarm.");
  if($alarm_action ne ""){send_alarm("storm", $stormrain);}; 
};
if($low_outtemp_alarm == 1){
  syslog("warning", "Low outdoor temperature alarm."); 
  if($alarm_action ne ""){send_alarm("low_outtemp", $outtemp);};
};
if($low_outtemp_alarm > 0 && ($low_outtemp_alarm % $alarm_interval) == 0){
  syslog("warning", "Low outdoor temperature alarm."); 
  if($alarm_action ne ""){send_alarm("low_outtemp", $outtemp);};
};
if($hi_outtemp_alarm == 1){
  syslog("warning", "High outdoor temperature alarm."); 
  if($alarm_action ne ""){send_alarm("hi_outtemp", $outtemp);};
};
if($hi_outtemp_alarm > 0 && ($hi_outtemp_alarm % $alarm_interval) == 0){
  syslog("warning", "High outdoor temperature alarm."); 
  if($alarm_action ne ""){send_alarm("hi_outtemp", $outtemp);};
};
if($windsp_alarm == 1){
  syslog("warning", "High wind gust alarm."); 
  if($alarm_action ne ""){send_alarm("windsp", $windsp);};
};
if($windsp_alarm > 0 && ($windsp_alarm % $alarm_interval) == 0){
  syslog("warning", "High wind gust alarm."); 
  if($alarm_action ne ""){send_alarm("windsp", $windsp);};
};
if($avgwindsp_alarm == 1){
  syslog("warning", "High wind speed alarm."); 
  if($alarm_action ne ""){send_alarm("avgwindsp", $avgwindsp);};
};
if($avgwindsp_alarm > 0 && ($avgwindsp_alarm % $alarm_interval) == 0){
  syslog("warning", "High wind speed alarm."); 
  if($alarm_action ne ""){send_alarm("avgwindsp", $avgwindsp);}; 
};
if($low_outdew_alarm == 1){
  syslog("warning", "Low outdoor dewpoint alarm."); 
  if($alarm_action ne ""){send_alarm("low_outdew", $dewpt);};
};
if($low_outdew_alarm > 0 && ($low_outdew_alarm % $alarm_interval) == 0){
  syslog("warning", "Low outdoor dewpoint alarm."); 
  if($alarm_action ne ""){send_alarm("low_outdew", $dewpt);};};
if($hi_outdew_alarm == 1){
  syslog("warning", "High outdoor dewpoint alarm."); 
  if($alarm_action ne ""){send_alarm("hi_outdew", $dewpt);};
};
if($hi_outdew_alarm > 0 && ($hi_outdew_alarm % $alarm_interval) == 0){
  syslog("warning", "High outdoor dewpoint alarm."); 
  if($alarm_action ne ""){send_alarm("hi_outdew", $dewpt);};
};
if($heat_alarm == 1){
  syslog("warning", "High heat index alarm."); 
  if($alarm_action ne ""){send_alarm("heat", $hi);};
};
if($heat_alarm > 0 && ($heat_alarm % $alarm_interval) == 0){
  syslog("warning", "High heat index alarm."); 
  if($alarm_action ne ""){send_alarm("heat", $hi);};
};
if($chill_alarm == 1){
  syslog("warning", "Low wind chill alarm."); 
  if($alarm_action ne ""){send_alarm("chill", $chill);};
};
if($chill_alarm > 0 && ($chill_alarm % $alarm_interval) == 0){
  syslog("warning", "Low wind chill alarm."); 
  if($alarm_action ne ""){send_alarm("chill", $chill);};
};
$trans_bat = hex("$data[87]"); 
if($trans_bat & 1){ $tid_0_low++; }else{$tid_0_low = 0; };
if($trans_bat & 2){ $tid_1_low++; }else{$tid_1_low = 0; };
if($trans_bat & 4){ $tid_2_low++; }else{$tid_2_low = 0; };
if($trans_bat & 8){ $tid_3_low++; }else{$tid_3_low = 0; };
if($trans_bat & 16){ $tid_4_low++; }else{$tid_4_low = 0; };
if($trans_bat & 32){ $tid_5_low++; }else{$tid_5_low = 0; };
if($trans_bat & 64){ $tid_6_low++; }else{$tid_6_low = 0; };
if($trans_bat & 128){ $tid_7_low++; }else{$tid_7_low = 0; };
if($tid_0_low == 1){syslog("notice", "The $tid{0} transmitter battery is low."); };
if($tid_0_low > 0 && ($tid_0_low % $alarm_interval) == 0){syslog("notice", "The $tid{0} transmitter battery is low."); };
if($tid_1_low == 1){syslog("notice", "The $tid{1} transmitter battery is low."); };
if($tid_1_low > 0 && ($tid_1_low % $alarm_interval) == 0){syslog("notice", "The $tid{1} transmitter battery is low."); };
if($tid_2_low == 1){syslog("notice", "The $tid{2} transmitter battery is low."); };
if($tid_2_low > 0 && ($tid_2_low % $alarm_interval) == 0){syslog("notice", "The $tid{2} transmitter battery is low."); };
if($tid_3_low == 1){syslog("notice", "The $tid{3} transmitter battery is low."); };
if($tid_3_low > 0 && ($tid_3_low % $alarm_interval) == 0){syslog("notice", "The $tid{3} transmitter battery is low."); };
if($tid_4_low == 1){syslog("notice", "The $tid{4} transmitter battery is low."); };
if($tid_4_low > 0 && ($tid_4_low % $alarm_interval) == 0){syslog("notice", "The $tid{4} transmitter battery is low."); };
if($tid_5_low == 1){syslog("notice", "The $tid{5} transmitter battery is low."); };
if($tid_5_low > 0 && ($tid_5_low % $alarm_interval) == 0){syslog("notice", "The $tid{5} transmitter battery is low."); };
if($tid_6_low == 1){syslog("notice", "The $tid{6} transmitter battery is low."); };
if($tid_6_low > 0 && ($tid_6_low % $alarm_interval) == 0){syslog("notice", "The $tid{6} transmitter battery is low."); };
if($tid_7_low == 1){syslog("notice", "The $tid{7} transmitter battery is low."); };
if($tid_7_low > 0 && ($tid_7_low % $alarm_interval) == 0){syslog("notice", "The $tid{7} transmitter battery is low."); };
$con_bat = hex("$data[89]$data[88]");
$con_bat = (($con_bat * 300) / 512) / 100;
$con_bat = sprintf("%.2f", $con_bat);
if($con_bat < 3.75){ $con_bat_low++; };
if($con_bat < $con_bat_min){ $con_bat_min = $con_bat; };
if($con_bat_low == 1){syslog("notice", "The console batteries are low.  Minimum voltage has been $con_bat_min V."); };
if($con_bat_low > 0 && ($con_bat_low % $alarm_interval) == 0){syslog("notice", "The console batteries are low.  Minimum voltage has been $con_bat_min V."); };
$forecasticon = hex("$data[90]");
$forecastrule = hex("$data[91]");
$sunrise = hex("$data[93]$data[92]");
$sunrise = sprintf("%04d", $sunrise);
$sunset = hex("$data[95]$data[94]");
@digits = split /(\d\d)/, $sunrise;
$sunrise = "$digits[0]$digits[1]:$digits[2]$digits[3]";
@digits = split /(\d\d)/, $sunset;
$sunset = "$digits[0]$digits[1]:$digits[2]$digits[3]";
#
# Calculate Dewpoints
#
$tempc = (5/9)*($outtemp-32);
$ews = $outhum*0.01*exp((17.502*$tempc)/(240.9+$tempc));
$num1 = 240.9*(log($ews));
$num2 = 17.5-(log($ews));
$dewpt = $num1/$num2;
$dewpt = (9/5)*$dewpt+32;
$dewpt = sprintf("%.1f", $dewpt);
if($dewpt < $min_dewpt){
        $min_dewpt = $dewpt;
        $min_dewpt_time = strftime "%H:%M:%S", localtime time;
	$new_extreme = 1;
};
if($dewpt > $max_dewpt){
        $max_dewpt = $dewpt;
        $max_dewpt_time = strftime "%H:%M:%S", localtime time;
	$new_extreme = 1;
};
$tempc = (5/9)*($intemp-32);
$ews = $inhum*0.01*exp((17.502*$tempc)/(240.9+$tempc));
$num1 = 240.9*(log($ews));
$num2 = 17.5-(log($ews));
$indewpt = $num1/$num2;
$indewpt = (9/5)*$indewpt+32;
$indewpt = sprintf("%.1f", $indewpt);
if($indewpt < $min_indewpt){
        $min_indewpt = $indewpt;
        $min_indewpt_time = strftime "%H:%M:%S", localtime time;
        $new_extreme = 1;
};
if($indewpt > $max_indewpt){
        $max_indewpt = $indewpt;
        $max_indewpt_time = strftime "%H:%M:%S", localtime time;
        $new_extreme = 1;
};
#
# Calculate wind chill
#
$chill = 35.74+(0.6215*$outtemp)-(35.75*($avgwindsp**0.16))+(0.4275*$outtemp*($avgwindsp**0.16));
if($avgwindsp < 3 || $outtemp > 50){ $chill = 100; };
$chill = sprintf("%.1f", $chill);
if($chill < $min_chill){
      $min_chill = $chill;
      $min_chill_time = strftime "%H:%M:%S", localtime time;
      $new_extreme = 1;
};
#
# Calculate Heat Index
#
if($outtemp > 77 && $outhum > 39){
      $hi = -42.379+(2.04901523*$outtemp)+(10.14333127*$outhum)-(0.22475541*$outtemp*$outhum)-(0.00683783*($outtemp**2))-(0.05481717*($outhum**2))+(0.00122874*($outtemp**2)*$outhum)+(0.00085282*$outtemp*($outhum**2))-(0.000001998*($outtemp**2)*($outhum**2));
};
if($outtemp < 77.1){ $hi = -100; };
if($outtemp > 77 && $outhum < 40){ $hi = -100; };
$hi = sprintf("%.1f", $hi);
if($hi > $max_hi){
      $max_hi = $hi;
      $max_hi_time = strftime "%H:%M:%S", localtime time;
      $new_extreme = 1;
};


=head1 Operational Characteristics

In most instances, the daemon collects the data provided by the weather station.  Some values like wind chill, heat index, and dewpoint are not provided and the daemon calculates these for you.  The daemon also checks the crc values on each packet received from the weather station, and if an error is detected, a notice level message is sent to the syslog and the packet is not processed.  If an obviously out of range value is detected within the packet, a notice is sent to the syslog and that value is not processed or used in any calculations.

In the case of the barometric trend, the daemon will calculate this in order to determine the rate of rise or fall in the barometer, thus allowing you to set a silent alarm threshold.  This information is provided by the Rev. B firmware, but it is ignored by the daemon.

In the case of wind direction, it takes the degree reading from the weather station and translates it into a more human friendly form that will be written into the database and the current and extremes files.  Examples:  NE instead of 45 degrees, ESE instead of 105 degrees, etc.  Also for internet site updates and for the daily obs file, it calculates the average direction of the wind during the last three minutes.  The gust that is reported to internet sites is the highest wind speed observed since the previous report.  The average wind speed (which is read from the console) is used as the basis for calculating the wind chill. 

The daemon does it's own calculation for the rainfall rate even though this is provided by the weather station.  I live in the Southwestern desert areas of the US, so this type of calculation makes sense for my climate.  It isn't likely to be that big of a deal or make that much difference in an area that receives more precipitation.  The calculation that I use does NOT require 2 "dumps" of the rain sensor within 15 minutes in order to register a rate like the rate provided on the console.  It also will not jump ridiculously high if you have a shower that dumps the sensor several times in a short period and then ends 5 minutes later.  I do record  the rate from the console in the current observations file so it is available if you wish to use it.  The data sent to the internet sites is the rate the daemon calculates, which is simply the actual amount of rain received in the previous 60 minutes, unless it is between midnight and 1 AM, then the rate reflects the amount of rain received since midnight.  

Because the database updates and the correct function of the rainfall rate calculations depend on a close syncronization between the time on the weather station and the time on the computer system, the daemon will syncronize the weather station console time with the computer system time at noon each day. 

The daemon also keeps track of the console and transmitter battery voltages and will write a notice to the syslog if the battery voltage drops too low.  This message will repeat at a rate controlled by the $alarm_interval variable until the condition is corrected.

The daemon now monitors what I think are the common alarms that may be set on your console.  You may also set silent versions of these alarms in the vanprod.conf file, except for the flash flood alarm.  The daemon will log a warning to your syslog when any alarms are triggered.  These messages will continue at a rate controlled by the alarm_interval setting in vanprod.conf.  The alarms monitored are:  falling barometer, rising barometer, low indoor temperature, high indoor temperature, low indoor humidity, high indoor humidity, high rain rate, 15 minute rainfall (aka flash flood alarm), 24 hour rain total, storm total rainfall, low outdoor temperature, high outdoor temperature, wind gust, wind speed (average), low outdoor dewpoint, high outdoor dewpoint, high heat index, low wind chill.  

The daemon will fork a child process to post the updates to internet sites and perform the database updates.  If the fork calls fail, the daemon will still perform these functions, just in a single threaded manner.

UV, leaf moisture, soil moisture, evapotranspiration, extra temperature and humidity readings from additional sensors, solar radiation, and alarms for these sensors are ignored.

=cut

# record our current extremes in a file clobbering old file.
if($new_extreme){
	if($min_chill == 100){ $min_chill = "--"; };
	if($max_hi == -100){ $max_hi = "--"; };
	$date = strftime "%m.%d.%Y", localtime time;
	open(EXTREMES, ">$directory/extremes.$date") or syslog("notice", "Cannot write to extremes file $directory/extremes.$date %m");
	print EXTREMES "$min_bar,$min_bar_time,$max_bar,$max_bar_time,$min_outtemp,$min_outtemp_time,$max_outtemp,$max_outtemp_time,$max_windsp,$max_winddir,$max_windsp_time,$min_outhum,$min_outhum_time,$max_outhum,$max_outhum_time,$min_dewpt,$min_dewpt_time,$max_dewpt,$max_dewpt_time,$min_chill,$min_chill_time,$max_hi,$max_hi_time,$max_rate,$max_rate_time,$dayrain,$yearrain,$min_intemp,$min_intemp_time,$max_intemp,$max_intemp_time,$min_inhum,$min_inhum_time,$max_inhum,$max_inhum_time,$min_indewpt,$min_indewpt_time,$max_indewpt,$max_indewpt_time,$rain24,$rain1";
	close(EXTREMES);
	$new_extreme = 0;
	if($min_chill eq "--"){ $min_chill = 100; };
	if($max_hi eq "--"){ $max_hi = -100; };
};

=pod

The daemon will generate 3 files in the directory that you specify in vanprod.conf.  These files are intended for use by other scripts or programs as opposed to being human readable even though they are plain text files.  This way tasks such as graphing or supplying information to a web page can be done independently of the daemon.  A brief description of each file's name, and contents follows.

F<extremes.mm.dd.yyyy>  This file contains the minimum and maximum values observed for a day.  The daemon always begins a new day at midnight.  This file always contains a single line of comma seperated values in this order:  minimum barometer and the time of observation, maximum barometer and the time of observation, minimum outdoor temp and time, maximum outdoor temp and time, maximum wind speed, direction and time, minimum outdoor humidity and time, maximum outdoor humidity and time, minimum outdoor dewpoint and time, maximum outdoor dewpoint and time, minimum wind chill and time, maximum heat index and time, maximum rainfall rate and time, and the daily rainfall and year to date rainfall totals, minimum indoor temp and time, maximum indoor temp and time, minumum indoor humidity and time, maximum indoor humidity and time, minimum indoor dewpoint and time, and maximum indoor dewpoint and time.

=cut

# record current observations in a file clobbering old file.  Append to daily file.
open(CURRENT, ">$directory/currentobs.$date") or syslog("notice", "Cannot write to current obervations file $directory/currentobs.$date %m");
if($chill == 100){ $chill = "--"; };
if($hi == -100){ $hi = "--"; };
print CURRENT "$hour,$minute,$sec,$bar,$outtemp,$avgwindsp,$windsp,$compdir,$outhum,$dewpt,$chill,$hi,$rate,$dayrain,$monrain,$yearrain,$sunrise,$sunset,$intemp,$inhum,$indewpt,$trend,$forecasticon,$forecastrule,$stormstart,$stormrain,$rain24,$rain1,$con_rate";
close(CURRENT);
if($chill eq "--"){ $chill = 100; };
if($hi eq "--"){ $hi = -100; };

=pod

F<currentobs.mm.dd.yyyy>  This file contains the following values from the most recent sample read from the station.  The values are on a single line and comma seperated in the order listed:  Hour of the day, minute, and second, barometer reading, outdoor temp, average wind speed, current wind speed, direction, outdoor humidity, outdoor dewpoint, wind chill, heat index, rainfall rate, daily rain, month to date rain, year to date rain, sunrise, sunset, indoor temp, indoor humidity, indoor dewpoint, barometric trend, forecast icon, forecast rule, storm start date, storm total rainfall, previous 24 hours rainfall, previous 1 hour rainfall,rainfall rate on the console.

F<dailyobs.mm.dd.yyyy>  This file is appended to once per minute and contains the then current observations for that minute on a single line.  The values are comma seperated and in the following order:  hour, minute, barometer, outdoor temp, average wind speed, wind gust for the previous 60 seconds, the average direction, outdoor humidity, outdoor dewpoint, wind chill, heat index, indoor temp, indoor humidity, indoor dewpoint, daily rain amount, 1 hour rainfall, and 24 hour rainfall.

Below is a translation of the forecast rule number to the text messages displayed on the Vantage Pro console.  Only the rule number is recorded in the current observations file.  Thanks to Tim Miller for providing these and doing some work on the forecast rule captures.

   0 = "Mostly clear and cooler."
   1 = "Mostly clear with little temperature change."
   2 = "Mostly clear for 12 hours with little temperature change."
   3 = "Mostly clear for 12 to 24 hours and cooler."
   4 = "Mostly clear with little temperature change."
   5 = "Partly cloudy and cooler."
   6 = "Partly cloudy with little temperature change."
   7 = "Partly cloudy with little temperature change."
   8 = "Mostly clear and warmer."
   9 = "Partly cloudy with little temperature change."
  10 = "Partly cloudy with little temperature change."
  11 = "Mostly clear with little temperature change."
  12 = "Increasing clouds and warmer. Precipitation possible within 24 to 48 hours."
  13 = "Partly cloudy with little temperature change."
  14 = "Mostly clear with little temperature change."
  15 = "Increasing clouds with little temperature change. Precipitation possible within 24 hours."
  16 = "Mostly clear with little temperature change."
  17 = "Partly cloudy with little temperature change."
  18 = "Mostly clear with little temperature change."
  19 = "Increasing clouds with little temperature change. Precipitation possible within 12 hours."
  20 = "Mostly clear with little temperature change."
  21 = "Partly cloudy with little temperature change."
  22 = "Mostly clear with little temperature change."
  23 = "Increasing clouds and warmer. Precipitation possible within 24 hours."
  24 = "Mostly clear and warmer. Increasing winds."
  25 = "Partly cloudy with little temperature change."
  26 = "Mostly clear with little temperature change."
  27 = "Increasing clouds and warmer. Precipitation possible within 12 hours. Increasing winds."
  28 = "Mostly clear and warmer. Increasing winds."
  29 = "Increasing clouds and warmer."
  30 = "Partly cloudy with little temperature change."
  31 = "Mostly clear with little temperature change."
  32 = "Increasing clouds and warmer. Precipitation possible within 12 hours. Increasing winds."
  33 = "Mostly clear and warmer. Increasing winds."
  34 = "Increasing clouds and warmer."
  35 = "Partly cloudy with little temperature change."
  36 = "Mostly clear with little temperature change."
  37 = "Increasing clouds and warmer. Precipitation possible within 12 hours. Increasing winds."
  38 = "Partly cloudy with little temperature change."
  39 = "Mostly clear with little temperature change."
  40 = "Mostly clear and warmer. Precipitation possible within 48 hours."
  41 = "Mostly clear and warmer."
  42 = "Partly cloudy with little temperature change."
  43 = "Mostly clear with little temperature change."
  44 = "Increasing clouds with little temperature change. Precipitation possible within 24 to 48 hours."
  45 = "Increasing clouds with little temperature change."
  46 = "Partly cloudy with little temperature change."
  47 = "Mostly clear with little temperature change."
  48 = "Increasing clouds and warmer. Precipitation possible within 12 to 24 hours."
  49 = "Partly cloudy with little temperature change."
  50 = "Mostly clear with little temperature change."
  51 = "Increasing clouds and warmer. Precipitation possible within 12 to 24 hours. Windy."
  52 = "Partly cloudy with little temperature change."
  53 = "Mostly clear with little temperature change."
  54 = "Increasing clouds and warmer. Precipitation possible within 12 to 24 hours. Windy."
  55 = "Partly cloudy with little temperature change."
  56 = "Mostly clear with little temperature change."
  57 = "Increasing clouds and warmer. Precipitation possible within 6 to 12 hours."
  58 = "Partly cloudy with little temperature change."
  59 = "Mostly clear with little temperature change."
  60 = "Increasing clouds and warmer. Precipitation possible within 6 to 12 hours. Windy."
  61 = "Partly cloudy with little temperature change."
  62 = "Mostly clear with little temperature change."
  63 = "Increasing clouds and warmer. Precipitation possible within 12 to 24 hours. Windy."
  64 = "Partly cloudy with little temperature change."
  65 = "Mostly clear with little temperature change."
  66 = "Increasing clouds and warmer. Precipitation possible within 12 hours."
  67 = "Partly cloudy with little temperature change."
  68 = "Mostly clear with little temperature change."
  69 = "Increasing clouds and warmer. Precipitation likley."
  70 = "Clearing and cooler. Precipitation ending within 6 hours."
  71 = "Partly cloudy with little temperature change."
  72 = "Clearing and cooler. Precipitation ending within 6 hours."
  73 = "Mostly clear with little temperature change."
  74 = "Clearing and cooler. Precipitation ending within 6 hours."
  75 = "Partly cloudy and cooler."
  76 = "Partly cloudy with little temperature change."
  77 = "Mostly clear and cooler."
  78 = "Clearing and cooler. Precipitation ending within 6 hours."
  79 = "Mostly clear with little temperature change."
  80 = "Clearing and cooler. Precipitation ending within 6 hours."
  81 = "Mostly clear and cooler."
  82 = "Partly cloudy with little temperature change."
  83 = "Mostly clear with little temperature change."
  84 = "Increasing clouds with little temperature change. Precipitation possible within 24 hours."
  85 = "Mostly cloudy and cooler. Precipitation continuing."
  86 = "Partly cloudy with little temperature change."
  87 = "Mostly clear with little temperature change."
  88 = "Mostly cloudy and cooler. Precipitation likely."
  89 = "Mostly cloudy with little temperature change. Precipitation continuing."
  90 = "Mostly cloudy with little temperature change. Precipitation likely."
  91 = "Partly cloudy with little temperature change."
  92 = "Mostly clear with little temperature change."
  93 = "Increasing clouds and cooler. Precipitation possible and windy within 6 hours."
  94 = "Increasing clouds with little temperature change. Precipitation possible and windy within 6 hours."
  95 = "Mostly cloudy and cooler. Precipitation continuing. Increasing winds."
  96 = "Partly cloudy with little temperature change."
  97 = "Mostly clear with little temperature change."
  98 = "Mostly cloudy and cooler. Precipitation likely. Increasing winds."
  99 = "Mostly cloudy with little temperature change. Precipitation continuing. Increasing winds."
 100 = "Mostly cloudy with little temperature change. Precipitation likely. Increasing winds."
 101 = "Partly cloudy with little temperature change."
 102 = "Mostly clear with little temperature change."
 103 = "Increasing clouds and cooler. Precipitation possible within 12 to 24 hours possible wind shift to the W, NW, or N."
 104 = "Increasing clouds with little temperature change. Precipitation possible within 12 to 24 hours possible wind shift to the W, NW, or N."
 105 = "Partly cloudy with little temperature change."
 106 = "Mostly clear with little temperature change."
 107 = "Increasing clouds and cooler. Precipitation possible within 6 hours possible wind shift to the W, NW, or N."
 108 = "Increasing clouds with little temperature change. Precipitation possible within 6 hours possible wind shift to the W, NW, or N."
 109 = "Mostly cloudy and cooler. Precipitation ending within 12 hours possible wind shift to the W, NW, or N."
 110 = "Mostly cloudy and cooler. Possible wind shift to the W, NW, or N."
 111 = "Mostly cloudy with little temperature change. Precipitation ending within 12 hours possible wind shift to the W, NW, or N."
 112 = "Mostly cloudy with little temperature change. Possible wind shift to the W, NW, or N."
 113 = "Mostly cloudy and cooler. Precipitation ending within 12 hours possible wind shift to the W, NW, or N."
 114 = "Partly cloudy with little temperature change."
 115 = "Mostly clear with little temperature change."
 116 = "Mostly cloudy and cooler. Precipitation possible within 24 hours possible wind shift to the W, NW, or N."
 117 = "Mostly cloudy with little temperature change. Precipitation ending within 12 hours possible wind shift to the W, NW, or N."
 118 = "Mostly cloudy with little temperature change. Precipitation possible within 24 hours possible wind shift to the W, NW, or N."
 119 = "Clearing, cooler and windy. Precipitation ending within 6 hours."
 120 = "Clearing, cooler and windy."
 121 = "Mostly cloudy and cooler. Precipitation ending within 6 hours. Windy with possible wind shift to the W, NW, or N."
 122 = "Mostly cloudy and cooler. Windy with possible wind shift o the W, NW, or N."
 123 = "Clearing, cooler and windy."
 124 = "Partly cloudy with little temperature change."
 125 = "Mostly clear with little temperature change."
 126 = "Mostly cloudy with little temperature change. Precipitation possible within 12 hours. Windy."
 127 = "Partly cloudy with little temperature change."
 128 = "Mostly clear with little temperature change."
 129 = "Increasing clouds and cooler. Precipitation possible within 12 hours, possibly heavy at times. Windy."
 130 = "Mostly cloudy and cooler. Precipitation ending within 6 hours. Windy."
 131 = "Partly cloudy with little temperature change."
 132 = "Mostly clear with little temperature change."
 133 = "Mostly cloudy and cooler. Precipitation possible within 12 hours. Windy."
 134 = "Mostly cloudy and cooler. Precipitation ending in 12 to 24 hours."
 135 = "Mostly cloudy and cooler."
 136 = "Mostly cloudy and cooler. Precipitation continuing, possible heavy at times. Windy."
 137 = "Partly cloudy with little temperature change."
 138 = "Mostly clear with little temperature change."
 139 = "Mostly cloudy and cooler. Precipitation possible within 6 to 12 hours. Windy."
 140 = "Mostly cloudy with little temperature change. Precipitation continuing, possibly heavy at times. Windy."
 141 = "Partly cloudy with little temperature change."
 142 = "Mostly clear with little temperature change."
 143 = "Mostly cloudy with little temperature change. Precipitation possible within 6 to 12 hours. Windy."
 144 = "Partly cloudy with little temperature change."
 145 = "Mostly clear with little temperature change."
 146 = "Increasing clouds with little temperature change. Precipitation possible within 12 hours, possibly heavy at times. Windy."
 147 = "Mostly cloudy and cooler. Windy."
 148 = "Mostly cloudy and cooler. Precipitation continuing, possibly heavy at times. Windy."
 149 = "Partly cloudy with little temperature change."
 150 = "Mostly clear with little temperature change."
 151 = "Mostly cloudy and cooler. Precipitation likely, possibly heavy at times. Windy."
 152 = "Mostly cloudy with little temperature change. Precipitation continuing, possibly heavy at times. Windy."
 153 = "Mostly cloudy with little temperature change. Precipitation likely, possibly heavy at times. Windy."
 154 = "Partly cloudy with little temperature change."
 155 = "Mostly clear with little temperature change."
 156 = "Increasing clouds and cooler. Precipitation possible within 6 hours. Windy."
 157 = "Increasing clouds with little temperature change. Precipitation possible within 6 hours. Windy"
 158 = "Increasing clouds and cooler. Precipitation continuing. Windy with possible wind shift to the W, NW, or N."
 159 = "Partly cloudy with little temperature change."
 160 = "Mostly clear with little temperature change."
 161 = "Mostly cloudy and cooler. Precipitation likely. Windy with possible wind shift to the W, NW, or N."
 162 = "Mostly cloudy with little temperature change. Precipitation continuing. Windy with possible wind shift to the W, NW, or N."
 163 = "Mostly cloudy with little temperature change. Precipitation likely. Windy with possible wind shift to the W, NW, or N."
 164 = "Increasing clouds and cooler. Precipitation possible within 6 hours. Windy with possible wind shift to the W, NW, or N."
 165 = "Partly cloudy with little temperature change."
 166 = "Mostly clear with little temperature change."
 167 = "Increasing clouds and cooler. Precipitation possible within 6 hours possible wind shift to the W, NW, or N."
 168 = "Increasing clouds with little temperature change. Precipitation possible within 6 hours. Windy with possible wind shift to the W, NW, or N."
 169 = "Increasing clouds with little temperature change. Precipitation possible within 6 hours possible wind shift to the W, NW, or N."
 170 = "Partly cloudy with little temperature change."
 171 = "Mostly clear with little temperature change."
 172 = "Increasing clouds and cooler. Precipitation possible within 6 hours. Windy with possible wind shift to the W, NW, or N."
 173 = "Increasing clouds with little temperature change. Precipitation possible within 6 hours. Windy with possible wind shift to the W, NW, or N."
 174 = "Partly cloudy with little temperature change."
 175 = "Mostly clear with little temperature change."
 176 = "Increasing clouds and cooler. Precipitation possible within 12 to 24 hours. Windy with possible wind shift to the W, NW, or N."
 177 = "Increasing clouds with little temperature change. Precipitation possible within 12 to 24 hours. Windy with possible wind shift to the W, NW, or N."
 178 = "Mostly cloudy and cooler. Precipitation possibly heavy at times and ending within 12 hours. Windy with possible wind shift to the W, NW, or N."
 179 = "Partly cloudy with little temperature change."
 180 = "Mostly clear with little temperature change."
 181 = "Mostly cloudy and cooler. Precipitation possible within 6 to 12 hours, possibly heavy at times. Windy with possible wind shift to the W, NW, or N."
 182 = "Mostly cloudy with little temperature change. Precipitation ending within 12 hours. Windy with possible wind shift to the W, NW, or N."
 183 = "Mostly cloudy with little temperature change. Precipitation possible within 6 to 12 hours, possibly heavy at times. Windy with possible wind shift to the W,
 NW, or N."
 184 = "Mostly cloudy and cooler. Precipitation continuing."
 185 = "Partly cloudy with little temperature change."
 186 = "Mostly clear with little temperature change."
 187 = "Mostly cloudy and cooler. Precipitation likely. Windy with possible wind shift to the W, NW, or N."
 188 = "Mostly cloudy with little temperature change. Precipitation continuing."
 189 = "Mostly cloudy with little temperature change. Precipitation likely."
 190 = "Partly cloudy with little temperature change."
 191 = "Mostly clear with little temperature change."
 192 = "Mostly cloudy and cooler. Precipitation possible within 12 hours, possibly heavy at times. Windy."
 193 = "FORECAST REQUIRES 3 HOURS OF RECENT DATA"
 194 = "Mostly clear and cooler."
 195 = "Mostly clear and cooler."
 196 = "Mostly clear and cooler."

Here is a listing of the forecast icon numbers.  Note that I only list each icon component. Add the values together to get the various icon combinations.  (Example 3 = Cloud with rain  1 (rain) + 2 (cloud) = 3)

  1 - Rain drops
  2 - Cloud
  4 - Part Sun (Small sun -- This never appears by itself)
  8 - Sun (Big bright sun)
 16 - Snow

=cut

if($prev_minute != $minute){
  if($chill == 100){ $chill = "--"; };
  if($hi == -100){ $hi = "--"; };
  print DAILY "$hour,$minute,$bar,$outtemp,$avgwindsp,$gust,$avgwinddir,$outhum,$dewpt,$chill,$hi,$intemp,$inhum,$indewpt,$dayrain,$rain1,$rain24\n";
  select(DAILY);
  $| = 1;  # force the buffer to flush
  $prev_minute = $minute;  # only write once per minute
  $gust = 0; # reset counters
  if($chill eq "--"){ $chill = 100; };
  if($hi eq "--"){ $hi = -100; };
};
}; # end sub
sub send_alarm {
  my $trigger = shift();
  my $var = shift();
  $value = `$alarm_action $trigger $var 2>&1`;
  if($value){syslog("warning", "$alarm_action:  $value"); };
};

=head1 EXAMPLES

Here are some examples of the contents of the files output by the daemon:

B<extremes.mm.dd.yy> (New lines added for better readability in this example)

30.01,16:59:02,30.12,00:00:02,24.7,07:13:22,53.9,14:45:51,24,WSW,14:53:02,22,
16:03:27,81,06:56:50,15.1,16:03:50,28.1,11:56:22,20.1,07:15:58,--,00:00:00,
0.00,00:00:02,0.00,14.19,67.0,07:00:01,77.7,13:10:02,9,16:24:59,24,01:45:00,
12.0,16:36:59,32.2,13:18:01,0.00,0.00

B<currentobs.mm.dd.yyyy>

18,46,45,30.02,42.1,6,5,WSW,50,24.8,38.3,--,0.00,0.00,1.81,14.19,06:25,18:12,73.3,14,21.3,ST,8,1,00/00/00,0.00,0.00,0.00,0.00

B<dailyobs.mm.dd.yyyy>

 18,30,30.01,43.8,5,6,255,45,23.9,40.9,--,73.8,12,18.1,0.00,0.00,0.00
 18,31,30.01,43.6,5,6,254,46,24.2,40.7,--,73.6,12,17.9,0.00,0.00,0.00
 18,32,30.01,43.5,5,6,254,46,24.1,40.6,--,73.5,12,17.8,0.00,0.00,0.00
 18,33,30.01,43.3,5,6,253,46,23.9,40.3,--,73.5,13,19.7,0.00,0.00,0.00
 18,34,30.01,43.3,5,6,252,46,23.9,40.3,--,73.3,13,19.5,0.00,0.00,0.00
 18,35,30.01,43.2,5,6,251,46,23.8,40.2,--,73.3,13,19.5,0.00,0.00,0.00
 18,36,30.01,43.1,5,6,251,47,24.3,40.1,--,73.3,13,19.5,0.00,0.00,0.00
 18,37,30.01,42.9,5,7,250,46,23.6,39.9,--,73.1,13,19.4,0.00,0.00,0.00
 18,38,30.01,42.9,5,6,249,47,24.1,39.9,--,73.1,13,19.4,0.00,0.00,0.00
 18,39,30.01,42.8,5,6,248,47,24.0,39.8,--,73.1,13,19.4,0.00,0.00,0.00
 18,40,30.01,42.6,5,6,247,47,23.8,39.5,--,73.1,13,19.4,0.00,0.00,0.00

=head1 BUGS AND LIMITATIONS

All of the values for sensors that are not on my station as well as alarms for these sensors are ignored.  Feel free to send me your requests for what you would like to see added or changed.  My e-mail address is stsander@sblan.net.  Even if you don't have any specific requests, I'd love to hear from you just to let me know that you have decided to use this daemon.  Like most any other piece of software there is probably an "undocumented feature" that I have overlooked.  If you find one of those, be sure to let me know about it.

=head1 CHANGES

B<1.1 - >	Added monitoring for the console battery level.
	Added monitoring of indoor temperature, humidity, and dewpoint.
	Added sanity checking for values that are obviously out of range.

B<1.2 - >	Improved sanity checks for out of range values.
	Integrated work done by Tim Miller on barometric trend and forecast rules.
	Calculate the barometric trend for stations with Rev. A firmware.  (auto-detected)
	Added monitoring for the various transmitter battery levels for wireless stations.
	Modified the wind chill calculation to follow the formula and guidelines from the NWS.  (I had left some cruft in the code from the earliest days of the program.)
	Added alarm bit processing.
	The storm total rainfall and storm start date are now recorded.

B<2.0>	Added updates to APRSWXNET/CWOP.
	Some minor bug fixes.
	Tracking of rainfall in the past 1 and 24 hours.
	Switched to using a vanprod.conf file, changed the behavior of a HUP signal and added handling of USR1 signal.
	The daemon no longer sets the heat index and wind chill values to the outdoor temp.  If these values should not be defined according to NWS formulas they are set to -- be aware of this if you parse any of the generated files.  Also you may need to modify your database specs for those two columns.  
	Added silent alarm capability.
	Added capability to call an external script in response to an alarm.
	Added loop ratio to increase accuracy of some calculated values.
	Added daily rain amount to dailyobs file.
	Added rainfall rate from the console to current obs file. 
	Improved average wind direction calculation

B<2.0.1>	Some minor tweaks and bug fixes.  Mostly in the APRSWXNET/CWOP message formatting.

B<2.1>	Added 1 hour and 24 hour rainfall totals to dailyobs file.
	Some tweaks on the barometer trend calculation.  The console actually tracks the barometer to a resolution of .001 and vanprod now does the same.  The data written to the files is now carried out to .001 but the database value still has a .01 resolution.  
        Improved the intelligence for rolling over to the next APRSWXNET/CWOP server in the event that one or more of them are down.
	Fixed bug where daily rain and max rate values were being set to the previous day's rain total at midnight but correct the rest of the day.  
	Fixed bug where 1 and 24 hour rain totals would not be completely zeroed out if the rain originally fell in a heavy downpour.  

=head1 OTHER NOTES AND THOUGHTS

Perhaps you have noticed that the barometer reading on your Vantage Pro often does not match a nearby trusted source such as an airport or NWS ASOS station.  It also doesn't seem to match up with barometer readings broadcast by local TV and/or radio stations.  Well, believe it or not, there are some complex mathmatical formulas and a simple answer behind all of this.  A friend and I spent the better part of two weeks chasing down and verifying as best we could what we found to be the answer.  Now before I go any farther into this, let me just state that what I am presenting here is my layman's understanding of all of this.  I am by no means a meterologist or a mathmatician.  The Vantage Pro calculates and displays "reduced", "corrected", or "mean" sea level pressure.  NWS ASOS stations and airport VOR's (and thusly local TV and radio) report an altimeter reading.  The two numbers are related, but now we get into the complex math.  Both numbers are derived from the actual station pressure, which the Vantage Pro measures.  To complicate matters, there is no standard formula for deriving the mean sea level pressure.  In fact, I came across at least nine different methods.  Each one has it's own inherent weaknesses and errors.  The one used by the Vantage Pro is similar to the one used by ASOS stations, but the ASOS stations do not routinely report this number.  In addition, the inherent weakness in this method is elevation.  From what I could tell, large errors can be expected at or above 5,000 feet, and in very cold or very warm temperatures.  For those wanting to know the formula, here it is:

Psl = Ps * (R)

where Psl is sea level pressure, Ps is the unadjusted reading sensed by the Davis barometer, and R is the reduction ratio.  What lies on the other side of an otherwise innocent looking equal sign from R is some calculus, differential equations, and so forth.  

So, ready for the simple answer now?  If you set your Vantage Pro elevation to 0, it will not use the above formula.  On a day when weather conditions are stable and there is a high pressure system in your area, set your elevation to 0 and then set the barometer to match the reading from a nearby trusted source.  The Vantage Pro will now use the formula to derive the altimeter reading, which has it's own share of mathmatical equations, but works well below 18,000 feet and it will match the numbers provided by your local NWS office and media.  


Now for some PAUSE stuff.

=head1 README

This daemon is written to communicate with a Davis Vantage Pro Weather Staion.

It will store the daily extreme values and their time of occurance in a database and update the weather underground and/or APRSWXNET/CWOP at a user configurable interval between once per hour and once per minute, or you can disable this feature altogether.   

It will generate 3 comma seperated text files as it runs.  These files are intended for use by other scripts.

It has the ability to call an external script in response to a user set weather alarm either on the station console or within the conf file settings.

Example of installation:

	cp vanprod-$VERSION /usr/local/sbin/vanprod
	cp vanprod.conf-$VERSION /etc/vanprod.conf
	pod2man /usr/local/sbin/vanprod /usr/local/man/man1/vanprod.1

Create a script to start the daemon for you at boot.  Modify the vanprod.conf file to suit your preferences and needs.

B<UPGRADING FROM PREVIOUS VERSIONS>

B<To upgrade from a 0.x or 1.0 version:>  Beginning with version 1.1, you will need to modify the database table if you have been using that feature in any of the 0.x or 1.0 versions.  You will need to add columns for the minimum and maximum indoor temperature, humidity, and dewpoint as well as the time of occurance for each.  See the section on the database setup for additional details.  

B<Upgrading from 1.x to 2.0:>  In addition to the steps above, (if applicable) you will need to obtain the vanprod.conf file along with the daemon itself and modify the settings in that file to suit your needs.  You may need to modify your database table from int(3) to char(3) for the wind chill and heat index values.

=head1 PREREQUISITES

The daemon requires the following at a minimum in order to run:

Device::Davis
Getopt::Std
Sys::Syslog
POSIX
Date::Calc
Date::Manip
LWP
Socket

=head1 COREQUISITES

C<DBI> for database updates.

=pod OSNAMES

any Unix / Linux variant or Mac (only tested with OS X)

=pod SCRIPT CATEGORIES

Networking
Web

=head1 SEE ALSO

perl(1) perlfunc(1) Device::Davis(3) POSIX(3) LWP(3) DBI(3) Date::Manip(1) Date::Calc(3) Getopt::Std(3) Sys::Syslog(3) syslog.conf(5) http://www.mysql.com/doc/

=head1 COPYRIGHT AND LICENSE

Copyright 2004, 2005 by Stan Sander.  stsander@sblan.net  You are welcome to send me any requests for new features or enhancements.

Vanprod is free software.  You may redistribute
it and/or modify it under the same terms as Perl itself.

=cut