Manual

Appendix
B
B-1
DF1 Diagnostic Command Support
The information in this appendix deals only with RS-232C DF1
communications, between the host processor and the Communications
Controller.
The Communications Controller interprets and responds to the following
diagnostic commands from the host processor:
Table B.A
Communications
Controller Diagnostic Commands
Description Command Byte Function Code (hex)
Diagnostic Loop 06 00
Diagnostic Read Counters 06 01
Diagnostic Status 06 03
Reset Diagnostic Counters 06 07
Diagnostic Loop
You can use this command to check the integrity of the transmissions over
the communication link. The command message transmits up to 243 bytes
of data to a node interface module. The receiving module should reply to
this command by transmitting the same data back to the originating node.
Figure B.1
Diagnostic
Loop Command Format
1 byte 1 byte 2 bytes 1 byte 243 bytes max
CMD
06
STS TNS FNC
00
DATA
Figure B.2
Diagnostic
Loop Reply Format
1 byte 1 byte 2 bytes 243 bytes max
CMD
46
STS TNS DATA
Diagnostic Command Support