On Tue, 2014-03-18 at 09:56 -0500, Tom Marchant wrote: > while s/370 was limited to 24-bit addressing > until XA in 1982 or 1983 began to support 31-bit addressing, not 32-bit like > the > model 67.
I vaguely remember the dual-address-space-facility that began life just before XA came around. There was some exploitation of it in - I think - MVS/SE2 (or was it SP1?). Here's an interesting paper: "Development and attributes of z/Architecture" from IBM's R&D Journal, July/September 2002: http://www.cl.cam.ac.uk/teaching/2006/CompArch/documents/all/processors/ibm360/ibm-z-plambeck.pdf -- David Andrews A. Duda & Sons, Inc. [email protected] ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
