• Please review our updated Terms and Rules here

Are there usable 4004 computer replicas?

Roland Huisman

Roland Huisman

Veteran Member
Joined
Mar 24, 2011
Messages
1,553
Location
The Netherlands
I have two boards with National semiconductor 4004 CPUs on it.

pro-log 4004.JPG

These boards are from an EPROM programmer which were built into a development machine. The machines are gone, the original programmer brand is pro-log. But to be honest, I don't care about the original boards, I just would like to do something nice with the 4004 chips on it.

So I was wondering if there are nice 4004 clone projects to built. Or are there any development boards which are worth cloning? And is there any nice software to run on it? Or is it better not to waste my time and put it on display in the display cabinet?

Regards, Roland
 
cool :) interesting to see the clock on the background. Taking hours and hours to boot or do something interesting...

It is fun, but I think I would like to build something more period correct... :unsure: And no, not a calculator ;)

I guess there is a 4004 monitor from those days. (like for the Intellec MCS-4/40) But is there any interesting software?
There has never been a big community like there was for the 8008
 
Even though the 1702 EPROMs on that board are awful to program and even to just use for reading, as compared to anything newer, it seems like your board has at least the bare minimum to be used as a simple 4004 system. If I were you I would probably try to figure out if the board generates it's own reset signal or if it needs an external reset signal, and then check the pinouts for all chips (except those that you already know only uses +5V and gnd) to figure out what voltages you need to run the board, and hook a suitable PSU to it, and see what happens.

In particular you could make an adapter that just removes all voltage rails except +5V in order to use newer EPROMs (or EEPROMs, preferably with a ZIF socket, to make the code-burn-test cycle faster).

On your PCB there are 4002 chips that are combined RAM and out ports, and there is a pair of 4008 and 4009 which are used to interface with standard EPROMs, and in some way they can also be used for RAM (but that RAM seems to be addressed in a different way as compared to the RAM in the 4002 chips).

Data sheets for all the 400x chips:
http://bitsavers.org/components/national/_dataSheets/FIPS_dataSheet.pdf
 
Using the board as-is, is a nice idea. I have piles of these 1702A roms and I have also a reader/programmer for it. I will see if I can find documentation.

My first idea was to clone a sbc kind of board. But I'm not familiar with these boards at the moment...
 
You have quite a bit of EPROM and I/O ports - but somewhat short on RAM (2 * 4002 = 2 * 320 bits = 640 bits = 160 nibbles of 4 bits each).

Seems good for an embedded system.

Christmas tree lights flasher, egg timer, reaction timer...

Possibly use it for driving a Z gauge model railway...

Dave
 
Roland Huisman said:
Using the board as-is, is a nice idea. I have piles of these 1702A roms and I have also a reader/programmer for it. I will see if I can find documentation.

My first idea was to clone a sbc kind of board. But I'm not familiar with these boards at the moment...
Click to expand...
Here's a board you could build.
 
Qbertnix said:
dmitry.gr

Linux/4004 - Dmitry.GR

Dmitry.GR: Slowly booting full Linux on the intel 4004 for fun, art, and absolutely no profit
dmitry.gr
Click to expand...

Man, that was a heck of a read. You’ve really got to be in it for the love of the game if you’re programming a 4004 to do *anything* today, let alone… that.

MiaM said:
Even though the 1702 EPROMs on that board are awful to program and even to just use for reading, as compared to anything newer, it seems like your board has at least the bare minimum to be used as a simple 4004 system.
Click to expand...

It does seem like all the parts are there for any reasonable DIY 4004 project. Transplanting them to a board that would let you use a more modern EEPROM would certainly be better if the plan is to actively play with 4004 programming, but yeah, at least it has those 4008/4009 interface chips instead of being hostage to a 4001 mask ROM.
 
Oh, I missed that the 1702 also has a weird pinout. In particular only 2 of 8 data lines match later 2716 and larger chips, so would need an adapter that requires a lot of signals.
 
daver2 said:
That is a nice board...

Dave
Click to expand...
Thanks. It used a 4201 for the clock and a 4289 for the memory and I/O interface. Looks like Roland’s board has the 4008/4009 for the memory interface. Pretty much the same functionality- the 4289 was a combined 4008/4009. A 4040 could also be run by installing it in the 24 pin socket (and removing the 4004 of course.) Handdrawn schematics exist but after 20 years and several moves may take a little digging.
 
You must log in or register to reply here.
Back
Top