IBM Mainframe Forum

Anyone have or seen (assembler) code to implement a z/os vtam 3270 program slu to programmatically logon to e.g. TSO? I successfully issue OPEN ACB, SETLOGON, REQSESS, OPNSEC, and RECEIVE macros to get an initial 3270 datastream logon screen image in storage, but any attempt to then provide a userid via a SEND macro and accompanying datastream is simply ignored. Very little such stuff (understandably) on the web. Thanks.

The manuals don't tell?

They do describe SEND in complete detail, of course. However, I've thrown innumerable variations of SEND parameters and values at the problem, to no avail. Can't figure what I'm missing.