Alan, You may have already read it but page 9 and 10 of the "MPA-II–A Multi-ProtocolTerminal EmulationAdapter Using the DP8344" document may be helpful.
It enumerates the 5250 commands but unfortunately doesn't list the command values. Also pages 47 and 48 of the "DP8344B Biphase Communications Processor–BCP" datasheet may be helpful with regard the message framing. Let me know if you have trouble finding these documents - I believe I found them on Bitsavers when I was looking into the 3270 protocol. Andrew
