1 Mar
2026
1 Mar
'26
1:47 p.m.
On Sun, 2026-03-01 at 15:32 -0600, Steve Lewis wrote:
Well, to clarify - my "amazement" was more
the idea of developing OS
software using paper (not as much the loading of one from paper,
though that is still a "glad I didn't have to do that" thing :).
So I'd characterize early OS development (meaning like 1956-1961) as:
developed "in memory" (e.g. CTSS is said to have been written in
FAP/MAD),
One of my colleagues (Theodore Pavlovich) was among the last to switch
from FAP to IBMAP. My mid-70's office partner (Suzanne Levison) had
worked on MAD as an undergraduate.
then the program exported to punch card (or punched
tape-- fan tape
being a bit later and fairly exclusive to the "DEC" ecosystem, as it
were). Once verified "yeah this kind of works", maybe that code
quickly migrated over to magtape (bearing it mind this was all pre-
ASCII standards). But one would need some kind of "bootloader" to
then initiate it from magtape.
The IBM 1401 has a "tape load" key. Oddly, the 1410 didn't. One needed
to key "L%U100011R_" into location 1 and set the instruction address to
00001.
On Sun, Mar 1, 2026 at 3:13 PM Van Snyder via cctalk
<cctalk(a)classiccmp.org> wrote:
> On Sun, 2026-03-01 at 13:13 -0700, ben via cctalk wrote:
> > I saw the ~5 drawers of punched cards that they used for this. I
> was
> > mortified at my mistake and expected that I was in BIG trouble.
> > Apparently the restore took most of the day.
>
> It took all day because the card reader on the 1130 was REALLY
> slow. My
> first full-time job was as a 1401 operator. The 1402 could read 600
> cards per minute, five minutes for a 3,000-card tray, 25 minutes
> for
> five of them.