I also agree, it looks like the MP7-03 with some I/O buffering. My guess is that the
connector on the back is similar to the interface to the SIM4-01. There would be address,
data and a strobe to do the programming.
The way it works on the SIN4 setup is that the programmer supplies the timing for the
pulses but the 4004 supplies the duration of the programming pulses. So the programming
sequence would be to hold the programming active for about 79 milliseconds then delay long
enough for pulses to stop before changing the address and data.
This would be a simple Arduino program.
Hopefully the programming signal is a low so that it would be in the read mode with
nothing driving it. Do remember, the 1702A is a PMOS part and is a hard pull up and a
weaker pull down, unlike TTL.
From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Jonathan Chapman via
cctalk <cctalk at classiccmp.org>
Sent: Saturday, October 30, 2021 8:03 PM
To: Chuck Guzis <cclist at sydex.com>; General Discussion: On-Topic and Off-Topic
Posts <cctalk at classiccmp.org>
Subject: Re: Mystery 1702A(?) EPROM Programmer
I assume the box is just a somewhat generic project enclosure, similar to standard
offerings from Bud, Hammond, etc.
I'll go through the power supply tomorrow or Monday and see where I can get with read
mode. It looks like writes should be hardware timed, so that's good news!
??????? Original Message ???????
On Saturday, October 30th, 2021 at 22:52, Chuck Guzis via cctalk <cctalk at
On 10/30/21 7:35 PM, Jonathan Chapman via cctalk
It's definitely not Intel, but I pulled the
control board and traced it a bit this afternoon. It seems to be very similar to the
circuit used on the Intel MP7-03 1702A programming module for the MCS-4/MCS-8 development
The colors aren't right for Intel, either. The scheme looks closer to
that of the Zilog MCZ.