Since there has been a mention of S/360 I/O architecture, I am reminded that almost precisely 35 years ago (I have a "marker" to "pin" my memory) I played a little game with the S/360 Model 20 where I discovered the Model 20 I/O interface. The programming ran on "bare boards", that is, without the carpet of the operating system, such as it was (what it was I totally forget). The I/O interface was rather different from that of the higher numbered S/360 models. The idea of the little game was to code the appropriate - what I later learned to call - "finite state machine" of point-to-point Binary Synchronous Communications (BSC). There were two programs, one to exercise outbound logic and one to exercise inbound logic. The outbound logic program multitasked with reading cards and the inbound with printing lines (and obeying print controls I expect). The unit record I/O instructions were at a very high level compared to their "older brothers" as were the communication line I/O instructions and I was able to concentrate on following the BSC protocols.
Incidentally, the partner programs were written using BATS/BTAM running on a more representative S/360. The manager in charge of the unit owning the Model 20 - bless him - thought I was doing some very useful research :-) Chris Mason ----- Original Message ----- From: "Shmuel Metz (Seymour J.)" <[EMAIL PROTECTED]> Newsgroups: bit.listserv.ibm-main To: <[email protected]> Sent: Wednesday, 15 February, 2006 5:04 PM Subject: Re: Mainframe Jobs Going Away > In <[EMAIL PROTECTED]>, on 02/14/2006 > at 06:56 PM, David Speake <[EMAIL PROTECTED]> said: > > >This stimulates. Why should they not be able to run > >UNIX/LINEX/AS400/Alpha-VMS or even Windows on Z chips without Z/OS or > >VM. > > 1. AIX/370 and IX/370 ran on older S/370 processorsl it wouldn't > take much to get them up on zSeries if the source code were > still around and somebody cared. > > 2. Linux *does* run on zSeries without Z/OS and VM, unless you count > PR/SM as being VM. > > 3. There is no support of the instruction sets used by OS/400, > windoze and VMS. > > 4. OS/400, windoze and VMS don't support the S/360 I/O architecture. > > Given the resources, you could certainly write some combination of > "microcode" and S/390 code to simulate AS/400 ML, DEC Alpha, DEC VAX > or Intel instruction sets and to simulate the foreign I/O > architectures. It's not clear that it would be worth the effort. > > >I saw some S/370 micro code listings about 30 years ago, but... > > AFAIK the zSeries puts a lot more hardware at the disposal of the > "microcode" and "millicode" than was the case on, e.g., the 3168. > > -- > Shmuel (Seymour J.) Metz, SysProg and JOAT > ISO position; see <http://patriot.net/~shmuel/resume/brief.html> > We don't care. We don't have to care, we're Congress. > (S877: The Shut up and Eat Your spam act of 2003) ---------------------------------------------------------------------- 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
