10 Apr
2024
10 Apr
'24
1:52 p.m.
On Wed, 2024-04-10 at 10:17 -0500, Jon Elson via cctalk wrote:
The
360/25 was a very interesting concept. The microcode was in
the top 16 KB of main storage,
360/30 microcode was in capacitive ROM, implemented using standard-size
punch cards with little metal rectangles that could be punched out to
make zeroes, sandwiched into metal backplanes. I remember a CE coming
out, running a few cards through a 026 to dup them, then installing
them. He didn't say whether he was repairing bugs in the 360
instruction set, or the 1401 emulation.