Fix PelcoP checksum calculation

2016-01-24 07:45:04 -06:00 · 2016-01-24 07:45:04 -06:00 · fa168027b3
parent 50b113cd02
commit fa168027b3
1 changed files with 3 additions and 1 deletions
--- a/scripts/ZoneMinder/lib/ZoneMinder/Control/PelcoP.pm
+++ b/scripts/ZoneMinder/lib/ZoneMinder/Control/PelcoP.pm
@ -133,8 +133,10 @@ sub sendCmd

    my $result = undef;

+    # Pelco P protocol checksum is created by XOR'ing the first seven bytes in the message
+    # including the first byte, the STX sync packet
    my $checksum = 0x00;
-    for ( my $i = 1; $i < int(@$cmd); $i++ )
+    for ( my $i = 0; $i < int(@$cmd); $i++ )
    {
        $checksum ^= $cmd->[$i];
    }