Avalue Technology VMS-BYT Quick Reference Manual page 93

Packing 7 will display only there is trouble code occurrence.
Packing7
Byte 0:"@",( 0x40)
Byte 1: " !",(0x21)
Byte 2: C1 (Low)
Byte 3: C1 (Hi)
Byte 4: C2 (Low)
Byte 5: C2 (Hi)
Byte 6: C3 (Low)
Byte 7: C3 (Hi)
Byte 8: C4 (Low)
Byte 9: C4 (Hi)
Byte 10: C5 (Low)
Byte 11: C5 (Hi)
Byte 12: 0
......
Byte 19: 0
Byte 20:
Check sum = Byte2
+ ..+Byte 19
Byte 21: 0x0D
Byte 22: 0x0A
NOTE :
1.) Taking the example trouble code.
EX:
40 21 94 04 12 15 23 0D
0D 0A Trouble code :
0494,
2.) Packing 7, Byte12~Byte19 not defined (set to ‖0‖)
20 0D 00 00 00 00 00 00 00 00 00 00 1C
1512, 0D23, 0D20 (HEX)
VMS-BYT Quick Reference Guide 93
Quick Reference Guide