And in HOME mode the instructions are fetched from the HOME address space. In all other cases they are fetched from the PRIMARY address space (though when XMS came out when executing in secondary mode some CPU models would fetch from the primary and others would fetch from the secondary).
On Fri, 18 Feb 2011 14:58:57 -0500 Kristine Harper <kristine.har...@neon.com> wrote: :>ASC mode is determined by PSW bits 16 and 17, and tells the system where to find the referenced data (the data referenced by the address in the GPRs). When ASC mode is secondary, SAC is 256 and you are in cross memory mode. And the data resides in the secondary address space. :> :>Kristine Harper :>IMS R&D :>NEON Enterprise Software :> :>-----Original Message----- :>From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Micheal Butz :>Sent: Thursday, February 17, 2011 2:35 PM :>To: IBM-MAIN@bama.ua.edu :>Subject: ASC. Mode :> :>Hi :> :>I know ASC mode refers to the Set Address Space Control instruction :> :>SAC. 0. Primary :> :>SAC 512 AR. Mode :> :>But what does it mean :> :>ASC mode: Primary or Secondry :> :>In the IBM manuals :> :> :> :>Sent from my iPhone :> :>---------------------------------------------------------------------- :>For IBM-MAIN subscribe / signoff / archive access instructions, :>send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO :>Search the archives at http://bama.ua.edu/archives/ibm-main.html :> :>---------------------------------------------------------------------- :>For IBM-MAIN subscribe / signoff / archive access instructions, :>send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO :>Search the archives at http://bama.ua.edu/archives/ibm-main.html -- Binyamin Dissen <bdis...@dissensoftware.com> http://www.dissensoftware.com Director, Dissen Software, Bar & Grill - Israel Should you use the mailblocks package and expect a response from me, you should preauthorize the dissensoftware.com domain. I very rarely bother responding to challenge/response systems, especially those from irresponsible companies. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
