E1 serial communication not exactly like B1

Currently my client has an AS/400 which talks to a B1 board over a serial link. In preparation for upgrading their system and using Ethernet for communication we installed an E1 board and connected the serial interface to the AS/400 just like the B1. In theory the AS/400 should communicate with the E1 just like it did with the B1 using the Optomux protocol. In practice things didn’t work so well.

I used a data scope to monitor communications both with the old B1 in place and then with the new E1 in place. The B1 traffic looks exactly like I expect as per the Optomux protocol documentation. The E1 however seems to send an extra reply message after the first command sent by the AS/400. This extra reply is throwing the AS/400 program off and things go downhill from there.

Portions of those communication logs with markups/comments are here:

  • http://dl.dropbox.com/u/3016655/OptoLogs/B1.pdf
  • http://dl.dropbox.com/u/3016655/OptoLogs/E1.pdf
(Sorry, I tried to attach these files to this forum post but was not successful.)

Updating the programming on the AS/400 is not an easy option. I’m hoping someone might be able to explain why the E1 is sending me the extra reply message and if there is a way I can make it behave more like the B1. Note that I have not connected the Ethernet interface at all yet. Once that interface is established can the E1’s behavior be configured in some manner with the Opto software?


Hi 3rady,
On this one, I strongly suggest you contact our Product Support Group, it’s FREE.