Z80 to S2650 Pod converter

This is a PCB based on an article in one of the Fluke magazines that explained how to make adapters to allow testing of boards based on processors for which Fluke pods were not available. The article takes a pod that has similar characteristics to the CPU required, and explains about converting the signals, and conveniently (for me), it ended with the full wiring for an S2650 adapter.

However, making one that would be compact enough to be usable and not have a mass of wires required a PCB, so here is my attempt at such a PCB. The picture shows the adapter in use on a bootleg 'The Invaders' PCB. (if Zaccaria's invader game was an unlicensed bootleg of 'Space Invaders', then that would make this PCB a bootleg of a bootleg!)

The functions that I have used all work as expected, and include BUS / READ / WRITE / ROM / RAM SHORT and RAM LONG. I expect that most of the other commands should work as well, but have not tried them yet. (obviously RUN UUT is not going to work!)

This shows the top of the board. visible are the logic chips used to do the necessary combination and other changes to control lines, and the socket where the Z80 fluke plugs in. To make it more rubust for continued use, I will probably fit a 40 pin ZIF socket into this socket at some point.

The side view shows the 40 pins and socket fitted to the other CPU slot. This is the connector that is plugged into the UUT, so again, I usually double up on sockets so if a pin gets damaged, then I can just replace that socket. (I also do this on the actual Fluke pods - it can save a lot of grief)

Also, just visible in the picture are the smoothing caps fitted underneath each TTL used, not sure if these are strictly necessary, but I had some handy so I put them on.

You can get a PCB from me, or download the Gerbers here and get your own made up (no warranty - it worked for me), then the parts you will need to populate the board with are as follows; -

U1 = 74LS00

U2 = 74S00

U3 = 74LS02

U4 = 74LS11

E$2 = 330r

E$3 = 1k

Ceramic cap near E$2 = 300pf

Smoothing Caps

 

some 40 pin sockets and some PCB pins

 

Here is the article that the PCB is based upon in DJVU format.