On Tue, 30 Jun 2026 at 12:47, Mark Henderson < [email protected]> wrote:
> I stumbled upon this in Ch 4 of POPS in connection with some strange > results I experienced when trying to do a MVCL from a dataspace whose > origin was zero. The doc is far from clear and, frankly, looks incomplete > so I'm wondering whether the subject is better described elsewhere. Note, I > understand I can change the dataspace origin but that's not the essence of > the question. > ZAD is part of PER, and would have to be enabled, or nothing happens. If it's enabled in PER then - roughly - if an address is derived from a base register containing 0, then a PER ZAD interrupt will occur. ZAD dates from 2010, so long postdates data spaces in general, and 0-origin ones in particular. What "strange results" are you encountering? Tony H. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
