Rockwell Automation 2755 Enhanced Decoder Series B - Manual (Page 280)

16–15 PCCC Host Commands
Publication 2755-833
0
5
STS= 00H
High Byte Low Byte
MSB LSB
1
3 2
4
CMD= 06H
Diagnostic Loop Command
0 STS= 00H
High Byte Low Byte
MSB LSB
2
4
Diagnostic Loop Reply
5
1
3
FNC=00H
CMD Reply = 46H
TNS
Diagnostic Loop Data
122 bytes maximum
TNS
Diagnostic Loop Data
(same data as in command)
Read Diagnostic Counters
The Read Diagnostic Counters command (CMD= 06H, FNC= 01H)
returns diagnostic counter values. The command structure looks like
this:
0 STS= 00H
High Byte Low Byte
MSB LSB
1
3 2
4
CMD= 06H
Read Diagnostic Counters Command
0 STS= 00H
High Byte Low Byte
MSB LSB
2
8
Read Diagnostic Counters Reply
5
1
3
FNC=01H
4
7 6
9 Msg ACK-Timeout/Retries Msg Retry Failures
Msg Replies: NAK-NoMemory Msg Recvd: NAK-NoMemory
Msg Replies: NAK-Solicit Msg Replies: NAK-TooBig
11
15
10
14
The reply returns values for ten diagnostic counters. The reply
format looks like this:
Bad Messages Received Msg Replies: NAK-NoService 13 12
CMD Reply = 46H
TNS
TNS
Total Message Packets Received (2 bytes)
Total Message Packets Transmitted (2 bytes)