loop.pl

   1 #!/usr/bin/perl
   2 use strict;
   3
   4 use v5.10.1;
   5
   6 use Mojolicious::Lite;
   7 use Serial;
   8 use Mojo::IOLoop;
   9 use Mojo::IOLoop::Stream;
  10 use Mojo::Transaction::WebSocket;
  11 #use Mojo::JSON  qw(decode_json encode_json);
  12 use JSON;
  13 use Debug;
  14 use SMGLog;
  15 use Math::Round qw(nearest);
  16 use File::Copy;
  17
  18 use constant pi => 3.14159265358979;
  19
  20 my $devname = "/dev/davis";
  21 my $datafn = ".loop_data";
  22 my $dataf;
  23
  24 my $poll_interval = 2.5;
  25 my $rain_mult = 0.2;                            # 0.1 or 0.2 mm or 0.01 inches
  26 my $tid;
  27 my $rid;
  28 our $did;
  29 my $nlcount;
  30 my $state = "ready";
  31 my $buf;
  32 my $dbg;
  33 my $ser;                                                        # the serial port Mojo::IOLoop::Stream
  34 my $last_min_h;
  35 my $last_hour_h;
  36
  37 our $json = JSON->new->canonical(1);
  38 our $WS = {};                                   # websocket connections
  39
  40 our $ld = {};
  41
  42 our $loop_count;                                # how many LOOPs we have done, used as start indicator
  43
  44 our     @crc_table = (
  45                                   0x0, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
  46                                   0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
  47                                   0x1231, 0x210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
  48                                   0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
  49                                   0x2462, 0x3443, 0x420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
  50                                   0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
  51                                   0x3653, 0x2672, 0x1611, 0x630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
  52                                   0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
  53                                   0x48c4, 0x58e5, 0x6886, 0x78a7, 0x840, 0x1861, 0x2802, 0x3823,
  54                                   0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
  55                                   0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0xa50, 0x3a33, 0x2a12,
  56                                   0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
  57                                   0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0xc60, 0x1c41,
  58                                   0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
  59                                   0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0xe70,
  60                                   0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
  61                                   0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
  62                                   0x1080, 0xa1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
  63                                   0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
  64                                   0x2b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
  65                                   0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
  66                                   0x34e2, 0x24c3, 0x14a0, 0x481, 0x7466, 0x6447, 0x5424, 0x4405,
  67                                   0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
  68                                   0x26d3, 0x36f2, 0x691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
  69                                   0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
  70                                   0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x8e1, 0x3882, 0x28a3,
  71                                   0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
  72                                   0x4a75, 0x5a54, 0x6a37, 0x7a16, 0xaf1, 0x1ad0, 0x2ab3, 0x3a92,
  73                                   0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
  74                                   0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0xcc1,
  75                                   0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
  76                                   0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0xed1, 0x1ef0
  77                                  );
  78
  79 our %bar_trend;
  80
  81 $bar_trend{-60} = "Falling Rapidly";
  82 $bar_trend{196} = "Falling Rapidly";
  83 $bar_trend{-20} = "Falling Slowly";
  84 $bar_trend{236} = "Falling Slowly";
  85 $bar_trend{0} = "Steady";
  86 $bar_trend{20} = "Rising Slowly";
  87 $bar_trend{60} = "Rising Rapidly";
  88
  89 our $ending = 0;
  90
  91 $SIG{TERM} = $SIG{INT} = sub {++$ending; Mojo::IOLoop->stop;};
  92 $SIG{HUP} = 'IGNORE';
  93
  94
  95 # WebSocket weather service
  96 websocket '/weather' => sub {
  97   my $c = shift;
  98   my $msg = shift;
  99   my $tx = $c->tx;
 100
 101   # Opened
 102   app->log->debug('WebSocket opened.');
 103   dbg 'WebSocket opened' if isdbg 'chan';
 104   $WS->{$tx} = $tx;
 105
 106   # send historical data
 107   $c->send($ld->{lasthour_h}) if exists $ld->{lasthour_h};
 108   $c->send($ld->{lastmin_h}) if exists $ld->{lastmin_h};
 109
 110   # disable timeout
 111   $c->inactivity_timeout(3615);
 112
 113   # Incoming message
 114   $c->on(
 115                  message => sub {
 116                          my ($c, $msg) = @_;
 117                          dbg "websocket: text $msg" if isdbg 'chan';
 118                  },
 119                  json => sub {
 120                          my ($c, $msg) = @_;
 121                          dbg "websocket: json $msg" if isdbg 'chan';
 122                  }
 123   );
 124
 125   # Closed
 126   $c->on(finish => sub {
 127     my ($c, $code, $reason) = @_;
 128     app->log->debug("WebSocket closed with status $code.");
 129         dbg 'webwocket closed with status $code' if isdbg 'chan';
 130         delete $WS->{$tx};
 131   });
 132 };
 133
 134 get '/' => {template => 'index'};
 135
 136
 137 dbginit();
 138 if (@ARGV) {
 139         dbgadd(@ARGV);
 140 }
 141 dbgadd('chan');
 142
 143 dbg '***';
 144 dbg "*** starting $0";
 145 dbg '***';
 146
 147 our $dlog = SMGLog->new("day");
 148 dbg "before next tick";
 149 Mojo::IOLoop->next_tick(sub { loop() });
 150 dbg "before app start";
 151 app->start;
 152 dbg "after app start";
 153
 154 write_ld();
 155 close $dataf if $dataf;
 156
 157 # move all the files along one
 158 copy "$datafn.oooo", "$datafn.ooooo";
 159 copy "$datafn.ooo", "$datafn.oooo";
 160 copy "$datafn.oo", "$datafn.ooo";
 161 copy "$datafn.o", "$datafn.oo";
 162 copy $datafn, "$datafn.o";
 163
 164
 165 dbg '***';
 166 dbg "*** ending $0";
 167 dbg '***';
 168
 169 exit 0;
 170
 171 ##################################################################################
 172
 173 sub loop
 174 {
 175
 176         open $dataf, "+>>", $datafn or die "cannot open $datafn $!";
 177         $dataf->autoflush(1);
 178
 179         read_ld();
 180
 181         dbg "last_min: " . scalar gmtime($ld->{last_min});
 182         dbg "last_hour: " . scalar gmtime($ld->{last_hour});
 183
 184         $did = Mojo::IOLoop->recurring(1 => sub {$dlog->flushall});
 185
 186         do_reopen($devname);
 187 }
 188
 189
 190
 191 sub on_read
 192 {
 193         my ($ser, $d) = @_;
 194         $buf .= $d;
 195         $d =~ s/([\%\x00-\x1f\x7f-\xff])/sprintf("%%%02X", ord($1))/eg;
 196         dbg "read added '$d' buf lth=" . length $buf if isdbg 'raw';
 197         if ($state eq 'waitnl' && $buf =~ /[\cJ\cM]+/) {
 198                 dbg "Got \\n" if isdbg 'state';
 199                 Mojo::IOLoop->remove($tid) if $tid;
 200                 undef $tid;
 201                 undef $buf;
 202                 $nlcount = 0;
 203                 $ser->write("LPS 1 1\n");
 204                 chgstate("waitloop");
 205         } elsif ($state eq "waitloop") {
 206                 if ($buf =~ /\x06/) {
 207                         dbg "Got ACK 0x06" if isdbg 'state';
 208                         chgstate('waitlooprec');
 209                         undef $buf;
 210                 }
 211         } elsif ($state eq 'waitlooprec') {
 212                 if (length $buf >= 99) {
 213                         dbg "got loop record" if isdbg 'chan';
 214                         chgstate('');
 215                         process($buf);
 216                         undef $buf;
 217                 }
 218         }
 219 }
 220
 221 sub start_loop
 222 {
 223         $nlcount = 1;
 224         dbg "start_loop writing $nlcount \\n" if isdbg 'state';
 225         $ser->write("\n");
 226         Mojo::IOLoop->remove($tid) if $tid;
 227         undef $tid;
 228         $tid = Mojo::IOLoop->recurring(0.6 => sub {
 229                                                                            if (++$nlcount > 10) {
 230                                                                                    dbg "\\n count > 10, closing connection" if isdbg 'chan';
 231                                                                                    do_reopen($devname);
 232                                                                                    return;
 233                                                                            }
 234                                                                            dbg "writing $nlcount \\n" if isdbg 'state';
 235                                                                            $ser->write("\n");
 236                                                                    });
 237         chgstate("waitnl");
 238 }
 239
 240 sub chgstate
 241 {
 242         dbg "state '$state' -> '$_[0]'" if isdbg 'state';
 243         $state = $_[0];
 244 }
 245
 246 sub do_reopen
 247 {
 248         my $name = shift;
 249         dbg "do reopen on '$name' ending $ending";
 250         unless ($ending) {
 251                 $ser = do_open($name);
 252                 start_loop();
 253                 chgstate('');
 254                 $nlcount = 0;
 255                 Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
 256         }
 257 }
 258
 259 sub do_open
 260 {
 261         my $name = shift;
 262
 263         $ser->close if $ser;
 264         undef $ser;
 265
 266         my $ob = Serial->new($name, 19200) || die "$name $!\n";
 267         dbg "streaming $name fileno(" . fileno($ob) . ")" if isdbg 'chan';
 268
 269         my $ser = Mojo::IOLoop::Stream->new($ob);
 270         $ser->on(error=>sub {dbg "serial $_[1]"; do_reopen($name) unless $ending});
 271         $ser->on(close=>sub {dbg "serial closing"; do_reopen($name) unless $ending});
 272         $ser->on(timeout=>sub {dbg "serial timeout";});
 273         $ser->on(read=>sub {on_read(@_)});
 274         $ser->start;
 275
 276         Mojo::IOLoop->remove($tid) if $tid;
 277         undef $tid;
 278         Mojo::IOLoop->remove($rid) if $rid;
 279         undef $rid;
 280         $rid = Mojo::IOLoop->recurring($poll_interval => sub {
 281                                                                            start_loop() if !$state;
 282                                                                    });
 283         chgstate('');
 284         $nlcount = 0;
 285
 286         return $ser;
 287 }
 288
 289 my @min;
 290 my @hour;
 291
 292 sub process
 293 {
 294         my $blk = shift;
 295         my $loo =  substr $blk,0,3;
 296         unless ( $loo eq 'LOO') {
 297                 dbg "Block invalid loo -> $loo" if isdbg 'chan'; return;
 298         }
 299
 300         my $tmp;
 301         my $temp;
 302         my $rain;
 303         my %h;
 304
 305         my $crc_calc = CRC_CCITT($blk);
 306
 307         if ($crc_calc==0) {
 308
 309                 # Common ones
 310                 $tmp = unpack("s", substr $blk,7,2) / 1000;
 311                 $h{Pressure} = nearest(1, in2mb($tmp));
 312
 313                 $tmp = unpack("s", substr $blk,9,2) / 10;
 314                 $h{Temp_In} = nearest(0.1, f2c($tmp));
 315
 316                 $temp  = nearest(0.1, f2c(unpack("s", substr $blk,12,2) / 10));
 317                 $h{Temp_Out}  = $temp;
 318                 if ($temp > 75 || $temp < -75) {
 319                         dbg "LOOP Temperature out of range ($temp), record ignored";
 320                         return;
 321                 }
 322
 323                 $tmp = unpack("C", substr $blk,14,1);
 324                 $h{Wind} = nearest(0.1, mph2mps($tmp));
 325                 $h{Dir}     = unpack("s", substr $blk,16,2)+0;
 326
 327                 my $wind = {w => $h{Wind}, d => $h{Dir}};
 328                 $wind = 0 if $wind == 255;
 329                 push @{$ld->{wind_min}}, $wind;
 330
 331                 $tmp = int(unpack("C", substr $blk,33,1)+0);
 332                 if ($tmp > 100) {
 333                         dbg "LOOP Outside Humidity out of range ($tmp), record ignored";
 334                         return;
 335                 }
 336                 $h{Humidity_Out} = $tmp;
 337                 $tmp = int(unpack("C", substr $blk,11,1)+0);
 338                 if ($tmp > 100) {
 339                         dbg "LOOP Inside Humidity out of range ($tmp), record ignored";
 340                         return;
 341                 }
 342                 $h{Humidity_In}  = $tmp;
 343
 344
 345                 $tmp = unpack("C", substr $blk,43,1)+0;
 346                 $h{UV} = $tmp unless $tmp >= 255;
 347                 $tmp = unpack("s", substr $blk,44,2)+0; # watt/m**2
 348                 $h{Solar} = $tmp unless $tmp >= 32767;
 349
 350                 #       $h{Rain_Rate}  = nearest(0.1,unpack("s", substr $blk,41,2) * $rain_mult);
 351                 $rain = $h{Rain_Day}   = nearest(0.1, unpack("s", substr $blk,50,2) * $rain_mult);
 352                 my $delta_rain = $h{Rain} = nearest(0.1, ($rain >= $ld->{last_rain} ? $rain - $ld->{last_rain} : $rain)) if $loop_count;
 353                 $ld->{last_rain} = $rain;
 354
 355                 # what sort of packet is it?
 356                 my $sort =  unpack("C", substr $blk,4,1);
 357                 if ($sort) {
 358
 359                         # Newer LOOP2 packet
 360                         $tmp = unpack("C", substr $blk,18,2);
 361                         #               $h{Wind_Avg_10} = nearest(0.1,mph2mps($tmp/10));
 362                         $tmp = unpack("C", substr $blk,20,2);
 363                         #               $h{Wind_Avg_2} = nearest(0.1,mph2mps($tmp/10));
 364                         $tmp = unpack("C", substr $blk,22,2);
 365                         #               $h{Wind_Gust_10} = nearest(0.1,mph2mps($tmp/10));
 366
 367                         #               $h{Dir_Avg_10} = unpack("C", substr $blk,24,2)+0;
 368                         $tmp = unpack("C", substr $blk,30,2);
 369                         $h{Dew_Point} = nearest(0.1, f2c($tmp));
 370
 371                 } else {
 372
 373                         # Older LOOP packet
 374                         $tmp = unpack("C", substr $blk,15,1);
 375                         #               $h{Wind_Avg_10} = nearest(0.1,mph2mps($tmp));
 376                         $h{Dew_Point}  = nearest(0.1, dew_point($h{Temp_Out}, $h{Humidity_Out}));
 377                         $h{Rain_Month}  = nearest(0.1, unpack("s", substr $blk,52,2) * $rain_mult);
 378                         $h{Rain_Year}  = nearest(0.1, unpack("s", substr $blk,54,2) * $rain_mult);
 379                 }
 380
 381                 my $ts = time;
 382                 my $s;
 383                 my $dayno = int($ts/86400);
 384                 if ($dayno > $ld->{last_day}) {
 385                         $ld->{Temp_Out_Max} = $ld->{Temp_Out_Min} = $temp;
 386                         $ld->{last_day} = $dayno;
 387                 }
 388                 $ld->{Temp_Out_Max} = $temp if $temp > $ld->{Temp_Out_Max};
 389                 $ld->{Temp_Out_Min} = $temp if $temp < $ld->{Temp_Out_Min};
 390
 391                 if ($ts >= $ld->{last_hour} + 1800) {
 392                         $h{Pressure_Trend}    = unpack("C", substr $blk,3,1);
 393                         $h{Pressure_Trend_txt} = $bar_trend{$h{Pressure_Trend}};
 394                         $h{Batt_TX_OK}  = (unpack("C", substr $blk,86,1)+0) ^ 1;
 395                         $h{Batt_Console}  = nearest(0.01, unpack("s", substr $blk,87,2) * 0.005859375);
 396                         $h{Forecast_Icon}  = unpack("C", substr $blk,89,1);
 397                         $h{Forecast_Rule}  = unpack("C", substr $blk,90,1);
 398                         $h{Sunrise}  = sprintf( "%04d", unpack("S", substr $blk,91,2) );
 399                         $h{Sunrise}  =~ s/(\d{2})(\d{2})/$1:$2/;
 400                         $h{Sunset}   = sprintf( "%04d", unpack("S", substr $blk,93,2) );
 401                         $h{Sunset}  =~ s/(\d{2})(\d{2})/$1:$2/;
 402                         $h{Temp_Out_Max} = $ld->{Temp_Out_Max};
 403                         $h{Temp_Out_Min} = $ld->{Temp_Out_Min};
 404
 405                         if ($loop_count) {      # i.e not the first
 406                                 my $a = wind_average(scalar @{$ld->{wind_hour}} ? @{$ld->{wind_hour}} : {w => $h{Wind}, d => $h{Dir}});
 407
 408                                 $h{Wind_1h} = nearest(0.1, $a->{w});
 409                                 $h{Dir_1h} = nearest(0.1, $a->{d});
 410
 411                                 $a = wind_average(@{$ld->{wind_min}});
 412                                 $h{Wind_1m} = nearest(0.1, $a->{w});
 413                                 $h{Dir_1m} = nearest(1, $a->{d});
 414
 415                                 ($h{Rain_1m}, $h{Rain_1h}, $h{Rain_24h}) = calc_rain($rain);
 416                         }
 417                         $ld->{last_rain_min} = $ld->{last_rain_hour} = $rain;
 418
 419                         $last_hour_h = {%h};
 420                         $s = genstr($ts, 'h', \%h);
 421                         $ld->{lasthour_h} = $s;
 422
 423                         $ld->{last_hour} = int($ts/1800)*1800;
 424                         $ld->{last_min} = int($ts/60)*60;
 425                         @{$ld->{wind_hour}} = ();
 426                         @{$ld->{wind_min}} = ();
 427
 428                         write_ld();
 429
 430                 } elsif ($ts >= $ld->{last_min} + 60) {
 431                         my $a = wind_average(@{$ld->{wind_min}});
 432                         my %save;
 433
 434                         push @{$ld->{wind_hour}}, $a;
 435
 436                         if ($loop_count) {      # i.e not the first
 437                                 my $rm;
 438
 439                                 $h{Wind_1m} = nearest(0.1, $a->{w});
 440                                 $h{Dir_1m} = nearest(1, $a->{d});
 441                                 ($h{Rain_1m}, $h{Rain_1h}, $h{Rain_24h}) = calc_rain($rain);
 442                         }
 443                         $ld->{last_rain_min} = $rain;
 444
 445                         $h{Temp_Out_Max} = $ld->{Temp_Out_Max};
 446                         $h{Temp_Out_Min} = $ld->{Temp_Out_Min};
 447
 448                         $last_min_h = {%h};
 449                         $s = genstr($ts, 'm', \%h);
 450                         $ld->{lastmin_h} = $s;
 451
 452                         $ld->{last_min} = int($ts/60)*60;
 453                         @{$ld->{wind_min}} = ();
 454
 455                         write_ld();
 456
 457                 } else {
 458                         my $o = gen_hash_diff($ld->{last_h}, \%h);
 459                         if ($o) {
 460                                 $s = genstr($ts, 'r', $o);
 461                         }
 462                         else {
 463                                 dbg "loop rec not changed" if isdbg 'chan';
 464                         }
 465                 }
 466                 output_str($s) if $s;
 467                 $ld->{last_h} = \%h;
 468                 ++$loop_count;
 469         } else {
 470                 dbg "CRC check failed for LOOP data!";
 471         }
 472         return;
 473 }
 474
 475 sub genstr
 476 {
 477         my $ts = shift;
 478         my $let = shift;
 479         my $h = shift;
 480
 481         my $j =  $json->encode($h);
 482         my ($sec,$min,$hr) = (gmtime $ts)[0,1,2];
 483         my $tm = sprintf "%02d:%02d:%02d", $hr, $min, $sec;
 484
 485         return qq|{"tm":"$tm","t":$ts,"$let":$j}|;
 486 }
 487
 488 sub output_str
 489 {
 490         my $s = shift;
 491         dbg $s;
 492 #       say $s;
 493         $dlog->writenow($s);
 494         foreach my $ws (keys $WS) {
 495                 my $tx = $WS->{$ws};
 496                 if ($tx) {
 497                         $tx->send($s);
 498                 } else {
 499                         delete $WS->{$tx};
 500                 }
 501         }
 502 }
 503
 504 sub gen_hash_diff
 505 {
 506         my $last = shift;
 507         my $now = shift;
 508         my %o;
 509         my $count;
 510
 511         while (my ($k, $v) = each %$now) {
 512                 if ($last->{$k} ne $now->{$k}) {
 513                         $o{$k} = $v;
 514                         ++$count;
 515                 }
 516         }
 517         return $count ? \%o : undef;
 518 }
 519
 520 sub dew_point
 521 {
 522         my $temp = shift @_;
 523         my $rh   = shift @_;
 524
 525         #  Using the simplified approximation for dew point
 526         #  Accurate to 1 degree C for humidities > 50 %
 527         #  http://en.wikipedia.org/wiki/Dew_point
 528
 529         my $dewpoint = $temp - ((100 - $rh) / 5);
 530
 531         # this is the more complete one (which doesn't work)
 532         #my $a = 6.1121;
 533         #my $b = 18.678;
 534         #my $c = 257.14;
 535         #my $ytrh = log(($rh/100) + ($b * $temp) / ($c + $temp));
 536         #my $dewpoint = ($c * $ytrh) / ($b - $ytrh);
 537
 538         return $dewpoint;
 539 }
 540
 541 sub CRC_CCITT
 542 {
 543     # Expects packed data...
 544     my $data_str = shift @_;
 545
 546         my $crc = 0;
 547         my @lst = split //, $data_str;
 548         foreach my $data (@lst) {
 549                 my $data = unpack("c",$data);
 550
 551                 my $crc_prev = $crc;
 552                 my $index = $crc >> 8 ^ $data;
 553                 my $lhs = $crc_table[$index];
 554                 #print "lhs=$lhs, crc=$crc\n";
 555                 my $rhs = ($crc << 8) & 0xFFFF;
 556                 $crc = $lhs ^ $rhs;
 557
 558
 559         }
 560
 561         return $crc;
 562 }
 563
 564 sub f2c
 565 {
 566         return ($_[0] - 32) * 5/9;
 567 }
 568
 569 sub mph2mps
 570 {
 571         return $_[0] * 0.44704;
 572 }
 573
 574 sub in2mb
 575 {
 576         return $_[0] * 33.8637526;
 577 }
 578
 579 sub wind_average
 580 {
 581         my ($sindir, $cosdir, $wind);
 582         my $count;
 583
 584         foreach my $r (@_) {
 585                 $wind += $r->{w};
 586                 $sindir += sin(d2r($r->{d})) * $r->{w};
 587                 $cosdir += cos(d2r($r->{d})) * $r->{w};
 588                 ++$count;
 589         }
 590
 591         my $avhdg = r2d(atan2($sindir, $cosdir));
 592         $avhdg += 360 if $avhdg < 0;
 593         return {w => nearest(0.1,$wind / $count), d => nearest(0.1,$avhdg)};
 594 }
 595
 596 # radians to degrees
 597 sub r2d
 598 {
 599     my $n = shift;
 600     return ($n / pi) * 180;
 601 }
 602
 603 # degrees to radians
 604 sub d2r
 605 {
 606     my $n = shift;
 607     return ($n / 180) * pi;
 608 }
 609
 610 sub calc_rain
 611 {
 612         my $rain = shift;
 613
 614         $ld->{rain24} ||= [];
 615
 616         my $Rain_1h = nearest(0.1, $rain >= $ld->{last_rain_hour} ? $rain - $ld->{last_rain_hour} : $rain); # this is the rate for this hour, so far
 617         my $rm = nearest(0.1, $rain >= $ld->{last_rain_min} ? $rain - $ld->{last_rain_min} : $rain);
 618         my $Rain_1m = nearest(0.1, $rm);
 619         push @{$ld->{rain24}}, $Rain_1m;
 620         $ld->{rain_24} += $rm;
 621         while (@{$ld->{rain24}} > 24*60) {
 622                 $ld->{rain_24} -= shift @{$ld->{rain24}};
 623         }
 624         my $Rain_24h = nearest(0.1, $ld->{rain_24});
 625         return ($Rain_1m, $Rain_1h, $Rain_24h);
 626 }
 627
 628 sub read_ld
 629 {
 630         return unless $dataf;
 631
 632         seek $dataf, 0, 0;
 633         my $s = <$dataf>;
 634         chomp $s;
 635         dbg "read loop data: $s" if isdbg 'json';
 636         $ld = $json->decode($s) if length $s;
 637
 638         # sort out rain stats
 639         my $c;
 640         if ($ld->{rain24} && ($c = @{$ld->{rain24}}) < 24*60) {
 641                 my $diff = 24*60 - $c;
 642                 unshift @{$ld->{rain24}}, 0 for 0 .. $diff;
 643         }
 644         my $rain;
 645
 646         if ($ld->{rain24}) {
 647                 $rain += $_ for @{$ld->{rain24}};
 648         }
 649
 650         $ld->{rain_24} = nearest(0.1, $rain);
 651         delete $ld->{hour};
 652         delete $ld->{min};
 653 }
 654
 655 sub write_ld
 656 {
 657         return unless $dataf;
 658
 659         seek $dataf, 0, 0;
 660         truncate $dataf, 0;
 661         $ld->{ts} = time;
 662         my $s = $json->encode($ld);
 663         dbg "write loop data: $s" if isdbg 'json';
 664         print $dataf "$s\n";
 665 }
 666
 667
 668 __DATA__
 669
 670 @@ index.html.ep
 671 % my $url = url_for 'weather';
 672 <!DOCTYPE html>
 673 <html>
 674   <head><title>DWeather</title></head>
 675   <body>
 676         <h1>DWeather</h1>
 677
 678     <script>
 679         var ws;
 680
 681         function process(key,value) {
 682                 var d = document.getElementById(key);
 683                 if (d !== null) {
 684                         d.innerHTML = value;
 685                 }
 686         }
 687
 688     function traverse(o) {
 689                 console.log(o);
 690                 for (var i in o) {
 691                         process(i, o[i]);
 692                         if (o[i] !== null && typeof(o[i])=="object") {
 693                                 traverse(o[i]);
 694                         }
 695                 }
 696         }
 697
 698
 699     ws = new WebSocket('<%= $url->to_abs %>');
 700     document.body.innerHTML += 'ws connecting to: <%= $url->to_abs %> type_of: ' + typeof(ws) + '<br>';
 701     if (typeof(ws) === 'object') {
 702                 ws.onmessage = function (event) {
 703                         var js = JSON.parse(event.data);
 704                         if (js !== null && typeof(js) === 'object') {
 705                                 traverse(js);
 706                         }
 707                 };
 708                 ws.onopen = function (event) {
 709                         ws.send('WebSocket support works! ♥');
 710                 };
 711         } else {
 712                 document.body.innerHTML += 'Webserver only works with Websocket aware browsers';
 713         }
 714
 715     </script>
 716
 717 <br><br>
 718 <table border=1 width=80%>
 719 <tr>
 720 <th>Time:<td><span id="tm"> </span>
 721 <th>Sunrise:<td><span id="Sunrise"> </span>
 722 <th>Sunset:<td><span id="Sunset"> </span>
 723 <th>Console Volts:<td><span id="Batt_Console"> </span>
 724 <th>TX Battery OK:<td><span id="Batt_TX_OK"> </span>
 725
 726 <tr>
 727 <th>Pressure:<td><span id="Pressure"> </span>
 728 <th>Trend:<td><span id="Pressure_Trend_txt"> </span>
 729
 730 <tr>
 731 <th>Temperature in:<td> <span id="Temp_In"> </span>
 732 <th>Humidity:<td> <span id="Humidity_In"> </span>
 733
 734 <tr>
 735 <th>Temperature out:<td> <span id="Temp_Out"> </span>
 736 <th>Min:<td> <span id="Temp_Out_Min"> </span>
 737 <th>Max:<td> <span id="Temp_Out_Max"> </span>
 738 <th>Humidity:<td> <span id="Humidity_Out"> </span>
 739 <th>Dew Point:<td> <span id="Dew_Point"> </span>
 740
 741 <tr>
 742 <th>Wind Direction:<td> <span id="Dir"> </span>
 743 <th>Minute Avg:<td> <span id="Dir_1m">  </span>
 744 <th>Speed:<td> <span id="Wind"> </span>
 745 <th>Minute Avg:<td> <span id="Wind_1m">  </span>
 746
 747 <tr>
 748 <th>Rain Hour:<td> <span id="Rain_1h"> </span>
 749 <th>Day:<td> <span id="Rain_Day"> </span>
 750 <th>24hrs:<td> <span id="Rain_24h"> </span>
 751 <th>Month:<td> <span id="Rain_Month"> </span>
 752 <th>Year:<td> <span id="Rain_Year"> </span>
 753 </table>
 754 </body>
 755 </html>