I have located the ROM set for the assembler as described in the MCS 4 manual.
This was written by Tom Pittman. I was told he created it in exchange for a
SIM4-01 with Intel. He was said to use these for a mail list for the Homebrew
Computer Club. The code is quite compact. It was a two pass assembler that was
in just the four 1702 EPROMs, 1K of 4004 code! I should note that it will not
run on a 4040 as the code takes advantage of the limited stack. He intentionally
over flows the stack at one point to redirect the code to do different things. I
believe it was to change the mode from first pass to second pass. It used as
much RAM as was installed on the SIM4-01 or SIM4-02. It was made to use a ASR33
with punch/reader. Source would be read in to do error checking and label
identification, on the first pass. It would punch out a line at a time as
reading. One would put the tape back in for the second pass and punch out BPNF
format, read to blow ROMs or EPROMs.

Dwight Elvey Jan 2023

