AB 485CIF Write Issue

Any insight into this issue would be appreciated.

I'm using an SLC 5/05 processor to send a 485CIF write msg to a NETENI Series D which in turn emails an alarm message. On triggering the 485CIF Write, the EN and ST bit are set (all others clear), the message is transmitted, email received, but after the timeout period, the ER and TO bit are set with the error code 37H "Message timed out in local processor"

Type: Peer-to-Peer
Read/Write: Write
TargetDevice: 485CIF
Local/Remote: Local
Control Block: N15:0
Control Length: 14

Comm Command: 485CIF Write
Data Table: ST16:0
Size Elements: 1
Channel: 0

Msg Timeout: 10
Data Offset: 0
Local Node: 50
Local/Remote: Local

Thanks - Walt

Are the Net-ENI and the SLC-5/05 on the same IP subnet ? Is there a router between them ?

One hypothesis is that the Net-ENI's PCCC-level response is being mis-routed. That would be weird because clearly the TCP-level connection is being made successfully.

Another hypothesis is that sending a String as the payload with a 485CIF message type is not handled gracefully by the Net-ENI. I figure it wouldn't be in the feature set if it didn't work, but stranger things have happened.

If you can get a network tap and Wireshark to capture the transaction you could get further.

Communication between the 5/05 and NET ENI is via the RS232 port - should have mention that in the original post.

Walt

Thanks for the clarification; I should have figured that out because the control data block is just 14 words.

Is the cable an ordinary 1761-CBL-PM02 ? What you're describing could just be a broken wire on the Rx pin for the SLC-5/05.

The PCCC command would be seen by the MicroLogix, and executed, but the SLC-5/05 would never get the Acknowledge bytes.

Are you running any other MSG instructions through the Net-ENI, or using it to access the SLC-5/05 from a separate Ethernet network ?

Yes, a 1761-CMB-PM02 - I'll try another cable. Only one MSG instruction to the Net-ENI but two others via Ethernet to Micrologix processors. Also have tried two other Net-ENIs with the same results.

Walt

Well, not the cable. As an experiment I changed the message timeout to 60 seconds. After 30 the DN bit was set. I guess the issue is the slow mail server I'm using to send text messages. Thanks for your help.

Walt