On Fri, 8 Feb 2008 13:36:08 -0800, Ron Hawkins <[EMAIL PROTECTED]> wrote:
>... >I don't recall the differences, but as long as I can remember >the way to cancel most things in TSO was to "reset then PA1" >or "Reset then ATTN" This was on real CRT and emulators. > >I don't recall RESET alone doing anything but unlocking the >terminal for the PA1 or ATTN. > >... 3270 device characteristics vs. SNA half-duplex datastream vs. TSO behaviour. Then add Tn3270 emulation on top. RESET on a real 3270 was (as I recall) a purely local process. It sends nothing. All 3270 emulators I've heard of treat it that way. It performs a "keyboard unlock". ATTN performs an interrupt to a half-duplex SNA data flow. It sends a SIGNAL RU back to the application event though the application is sending. This is (if not always) interpretted by TSO as a PA1. PA1 - the 3270 AID character you are trying to give TSO. A non-SNA 3270 device could be (always was?) full duplex so the PA1 could be given to TSO without an ATTN. The half-duplex nature of SNA 3270 introduced the need for ATTN because it would interrupt the half-duplex flow. It is still up to TSO and/or the application running on it to process the PA1 or ATTN. Pat O'Keefe ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
