9 Feb
2026
9 Feb
'26
7:26 p.m.
a 2540 card read/punch was normally addressed as 00C/00D, a 1401 class
printer as 00F. if you had multiples, they were typically 01C/01D and 00E.
I heard, but never saw that if you didn't like the next operator, you taped
over the tabs that stop the cards on a 2501 card reader and the cards would
to shooting across the room.
Early on, there was a TOS as well as DOS that would run from one tape
drive. I tried to get a copy, but as just an operator, unable to. i
wonder if any copies exist.
we briefly had a 3rd party drive for 1311 disks, which was cool because it
had binary lights to show what track the head was on. We also had a 3rd
party extra 32k memory expansion for a model 30. they pulled that and
upgraded to a model 40 to get the bigger memory. The memory was needed for
sort tables when sorting checks (it was a bank).
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On Sun, Feb 8, 2026 at 9:19 AM Paul Koning via cctalk <cctalk(a)classiccmp.org>
wrote:
--
--Carey
On Feb 7, 2026, at 3:57 PM, Donald Whittemore via
cctalk <
cctalk(a)classiccmp.org> wrote:
My Dad was a 360 operator, as was I. I will swear he set the load unit
as 00C and hit load. In the card reader was something labeled CID.
Compatibility Initialization Deck. Was less than 1/2 inch of cards. I
believe it put the Mod 30 (or 40) into pure 1401 mode. No 360 code running.
You can certainly IPL off the card reader, though I've never done it. I
did see the 360 model 44 "emulator" deck, which is loaded that way using
the "Emulator IPL" button, into a separate block of memory invisible during
normal execution. It's vaguely like Alpha PALcode, I guess.
That deck was a standard IBM 360 object program file, with the channel
program on the first card loading all the pieces to the right places.
No idea what this CID was. It could be simply a "bare metal" ordinary 360
program, or a 360 program combined with helper microcode.
paul