> -Original Message-
> From: IBM Mainframe Assembler List l...@listserv.uga.edu> On Behalf Of Seymour J Metz
> Sent: 20 December 2020 17:12
> To: ASSEMBLER-LIST@LISTSERV.UGA.EDU
> Subject: Re: S/360 emulation in PC/370
>
> The 360/30, 360/40 and 360/50 had integrated channels, cycle steal
The 360/30, 360/40 and 360/50 had integrated channels, cycle stealing from the
CPU microcode. The channel-control unit-device structure was very similar to
that of the 7000 series and the 7030. When the S/360 came out, channel I/O was
the norm, and Interrupts go back to the 1950s.
Small machine
Shmuel, all
Well it is true that 360 I/O involved a separate channel processor that
shared memory with instruction processor, and it required handling
interrupts to determine status of I/O request.
Some computers just had byte I/O handled by instruction processor.
Don Higgins
d...@higgins.net
www
Any idea why Peter found S/360 I/O alien? I certainly thought that it was
conventional when it came out.
--
Shmuel (Seymour J.) Metz
http://mason.gmu.edu/~smetz3
From: IBM Mainframe Assembler List [ASSEMBLER-LIST@LISTSERV.UGA.EDU] on behalf
of Don Higgi
