Rockwell Automation 1770-KF2 Data Highway or Highway Plus Interface Module User Manual - Manual (Page 89)

Message Packet Formats
Chapter 5
5-10
Diagnostic Loop
You can use this command to check the integrity of transmissions over the
communication link. The command message transmits up to 243 bytes of
data to a station interface module. The receiving module should reply to
this command by transmitting the same data back to the originating
station.
Command Format:
Reply Format:
TNS STS CMD
06
SRC DST FNC
00
TNS STS CMD
46
SRC DST
DATA — Max. 243 Bytes
DATA — Max. of 243 Bytes
Diagnostic Read
This command reads up to 244 bytes of data from the PROM or RAM of
the station interface module. You can use it to read the module’s
diagnostic timers and counters. Except for the PLC-5, you must use the
diagnostic status command to obtain the starting address of the diagnostic
counters. The PLC-5 doesn’t require that this address be specified,
though you must include a dummy value in the ADDR field, which the
PLC-5 will ignore.
Command Format:
Reply Format:
TNS STS CMD
06
SRC DST FNC
01
TNS STS CMD
46
SRC DST
ADDR
DATA — Max. of 244 Bytes
SIZE