protocol_decode

diff --git a/Protocol.pm b/Protocol.pm
index 2db4ddb..829b7f0 100644 (file)
--- a/Protocol.pm
+++ b/Protocol.pm
@@ -5,7 +5,7 @@ use strict;
 require Exporter;
 
 our @ISA = qw(Exporter);
-our @EXPORT = qw( modbus_crc16 $protocol read_parameter_frame write_parameter_frame );
+our @EXPORT = qw( modbus_crc16 $protocol read_parameter_frame write_parameter_frame $function_code_description hex_dump protocol_decode );
 
 use Data::Dump qw(dump);
 
@@ -123,6 +123,148 @@ sub write_parameter_frame {
 
        return $frame . modbus_crc16($frame);
 }
+
+our $function_code_description = {
+       up => {
+               0x07 => 'Upstream Heartbeat Frame',
+               0x08 => 'Upstream alarm frame',
+               0x03 => 'Upstream Read Parameter Frame',
+               0x06 => 'Upstream return write parameter frame',
+       },
+       down => {
+               0x03 => 'Downstream read parameter frame',
+               0x06 => 'Downstream write parameter frame',
+       }
+};
+
+sub hex_dump {
+       my $bin = shift;
+       my $hex = unpack('H*', $bin);
+       $hex =~ s{(..)}{$1 }g;
+       return $hex;
+}
+
+sub protocol_decode {
+       my ( $up_down, $bin ) = @_;
+
+       $SIG{__WARN__} = sub {
+               return unless $debug;
+               print STDERR @_;
+       };
+
+       my $hash = {
+               up_down => $up_down,
+               bin => $bin,
+       };
+
+       my $cksum = substr($bin, -2, 2);
+
+       if ( my $crc = modbus_crc16( substr($bin,0,-2) ) ) {
+               if ( $crc ne $cksum ) {
+                       $hash->{error}->{crc} = "got " . unpack('H*',$crc) . " expected " . unpack('H*',$cksum);
+               }
+       }
+
+       my ( $header, $ver, $function_code, $len ) = unpack("CCCv", $bin);
+
+       $hash->{function_code} = $function_code;
+       $hash->{ver} = $ver;
+       $hash->{len} = $len;
+
+       my $data = substr($bin,5,-2);
+
+       warn "header = $header 0x", hex_dump($header)," ver = $ver function_code = $function_code len = $len == ",length($data), " data = ",hex_dump($data), " cksum = ", unpack('H*',$cksum);
+
+       if ( $header != 0x5a ) {
+               $hash->{error}->{header} = "$header expected 0x5a";
+       }
+
+       my $length_data = length($data);
+       if ( $length_data != $len ) {
+               $hash->{error}->{length} = "$length_data expected $len";
+       }
+
+
+       while ( $data ) {
+
+               warn "XXX data = ", hex_dump($data);
+
+               my $data_id = unpack( 'C', substr($data,0,1) );
+
+               if ( ! exists( $protocol->{$data_id} ) ) {
+                       my $len = unpack('C', substr($data,1,1));
+                       push @{ $hash->{error}->{data_id} }, sprintf "data_id %d 0x%2x len %d [%s]", $data_id, $data_id, $len, unpack('H*', substr($data,2,$len));
+                       $data = substr($data,2 + $len);
+                       next;
+               }
+               my $pack_fmt = $protocol->{$data_id}->{pack_fmt} || die "can't find pack_fmt for data_id $data_id";
+
+               my $data_range;
+               my $data_len;
+
+               if ( $data_id == 0x00 ) {
+                       # sequence number
+
+                       $data_range = substr($data,2,4);
+                       $data = substr($data,6);
+
+               } elsif ( $up_down eq 'down' && $function_code == 0x03 ) {
+                       # type A
+
+                       $data_range = substr($data,0,1);
+                       $data = substr($data,1);
+
+               } elsif ( $up_down eq 'up'   && ( $function_code == 0x07 || $function_code == 0x08 || $function_code == 0x03 ) ) {
+                       # type B
+
+                       $data_len = unpack('C', substr($data,1,1));
+                       $data_range = substr($data,2, $data_len);
+
+                       $data = substr($data,2 + $data_len);
+
+               } elsif ( $up_down eq 'down' && $function_code == 0x06 ) {
+                       # type B
+
+                       $data_len = unpack('C', substr($data,1,1));
+                       $data_range = substr($data,2, $data_len);
+
+                       $data = substr($data,2 + $data_len);
+
+               } elsif ( $up_down eq 'up' && $function_code == 0x06 ) {
+                       # type C
+
+                       # FIXME check first byte?
+                       my $data_range = substr($data,1,1);
+
+                       $data = substr($data,2);
+
+               } else {
+                       $hash->{error}->{function_code_unknown} = $function_code;
+                       warn "ERROR unknown function_code = $function_code";
+               }
+
+               my @v = unpack($pack_fmt, $data_range);
+
+               my $v = join(' ', @v);
+
+               if ( $data_id == 0x0c ) {
+                       $v = $v / 100;
+               } elsif ( $data_id == 0x0d ) {
+                       $v = $v / 100;
+               }
+
+               push @{ $hash->{data_id_order} }, $data_id;
+               $hash->{data_id}->{$data_id} = $v;
+               $hash->{data_len}->{$data_id} = $data_len;
+               $hash->{data_range}->{$data_id} = $data_range;
+
+       }
+
+       return $hash;
+
+} # protocol_decode
+
+
 1;
 
 # 6. Protocol Format