View Full Version : Ithaca Audio IA-1010 Rev 2 with JAIR8080 as I/O board works like a charm.

January 27th, 2017, 01:08 PM
Long story, and mostly done for fun...

So i built an IA-1010 rev 2. running at 2.0 mhz. Works great, I hacked a bit so it will support a 2732 eprom, instead of a 2708. I added remote rom disable circuitry via PIN 70 (unused) on the board. Along with this board I build from scratch a 64K ram card using 2 32K x 8 static rams, and also built a serial card based on the JAIR8080 by Josh Bensadon. It all worked great. Josh created a simplified serial monitor based on his JAIR8080 monitor, everything was working great. :)

Then I decided to add the SD interface to the serial card so I could run CP/M and keep hex files on it. The SD card interface was also lifted from the JAIR 8080 schematic. I used pin 70 on my homemade card to control the IA-1010 rom enable circuit as it needed to be disabled once the bios.hex was loaded. That too worked. Josh provided a lot of help with all that, and so did my RIGOL DS1154 scope 4 channels came in handy!

So it was time to move onto getting the SD part to work. I'm currently at that stage. Wired up the same as the JAIR and checked but I'm having some kind of noise issue with my point to point wiring? Either way hoping to work through that...

Each home made board I built has a few issues, and I was able to (sometimes with lots of help) work them out. :) (just the sd interface needs work)
Then I thought, Heck this would be a good time to setup a JAIR8080 as a dual serial and parallel card, with built in SD interface, and take a break from trouble shooting my home made board.

I removed my home made ram, serial IO and SD card board, and replaced it all with the JAIR8080 board without it's 8080 chip installed. Then I jumpered as per the manual, as RAM/ROM and I/O. I removed the Eprom from the IA-1010 because now I did not need it (or the mod to it) and switched on the system, rest and then run, and it booted up and it worked like a charm first try.

The JAIR8080 works perfectly with the IA-1010, if you want to play with a Z80 instead of an 8080.

It would be nice to figure out what is up with my home made JAIR SD interface, but in the mean time, I can enjoy Z80 goodness with JAIR8080 RAM/ROM I/O and sd card interface for CP/M :).

(still hoping to figure out why the sd interface of my home made card is not working i will update if I sort that out.)

here are pics of the Ram Card, the Serial Card, and the Serial Card with I/O and SD card interface...


and pic's of the Ithaca Audio card:


Cheers. :)