10 Feb
2023
10 Feb
'23
6:56 p.m.
CDL was for designing wired circuit boards, not integrated circuits..
It was used to design the Datakit switch, the Belle chess machine and
other hardware.
I suspect the cited IC-design tool was one that Steve Johnson created
for use in a short course that Carver Mead taught at Bell Labs. I am
not aware that it saw use outside of that course.
Doug
On Fri, Feb 10, 2023 at 12:37 AM Christian Dreier via TUHS
<tuhs(a)tuhs.org> wrote:
Hello there,
I recently watched an old Unix promotion video by AT&T on YouTube (AT&T
Archives: The UNIX Operating System: https://youtu.be/tc4ROCJYbm0) and
they mention a design tool for integrated circuits (apparently named
L-Gen or lgen; timestamped link: https://youtu.be/tc4ROCJYbm0?t=1284).
Part of this software is a language implemented with YACC that appears
to describe the behavior of digital logic, like modern hardware
description languages, i.e. Verilog and VHDL.
Does anyone have information about this, in particular:
- Documentation
- Which projects were realized with this?
- Source code, if possible
I asked this question on retrocomputing.stackexchange.com (see
https://retrocomputing.stackexchange.com/q/26301/26615) but so far there
is no satisfying answer. A "Circuit Design Language" (CDL) is mentioned
and there is some good information about it but it has another syntax
(as shown in the video vs. the documentation about CDL) and apparently
another purpose (description of board wiring vs. logic behavior).
Best regards,
Christian