Ithaca Audio IA-1130 PCB

[Wave Solder]

Hello, I have here a blank S-100 PCB made by Ithaca Audio marked IA-1130 and I wondered what the function of the board would be. There is a 40 pin DIP IC on it that has +5V going to pin 2 and ground connecting to pins 1,5 and 14.

I found a few pictures on Worthpoint.com website of a completed board but the main IC markings are not clear to give any clues.

1978 Ithaca Audio 1A 1130 Rev A Board | #2004412753

1978 Ithaca Audio 1A 1130 Rev A BoardDisclaimer: I AM NOT A COMPUTER PERSON. Please don't email me to yell at me about how little I know about this stuff! However, I'm happy to revise listing based on

www.worthpoint.com

Any information would be gratefully received..

 

[Altomare]

Could it be a Motorola 6820-based floppy disk controller? These type of AMI chips are usually second source Motorola 6800 and peripherals. I'm thinking S6820P but pinout doesn't match...
I'm still assuming it's a floppy board with a little boot RIL. Dumping the ROM could help too

Can you take pictures of both sides of your board?

 

[Wave Solder]

Here are shots of both sides of the PCB, sadly I don't have the ROM to dump the contents

 

[hmb]

This was Ithaca Audio's first floppy controller board, sold as a bare board for the hobbyist market. The 40-pin IC is likely an AMI S2350 USRT, repurposed to encode and decode data to a single-density floppy drive. The S2350 pinout matches the pin connections on the IA-1130, with Vcc on pin 2 and ground on pin 1. In this application pin 5 (CS*) and 14 (RESET) could be tied to ground. The original Heathkit H8 floppy controller (also released in 1977) used the S2350 for the same purpose.

 

[Wave Solder]

Thank you for that, it is great to get a mystery solved. Hopefully one day the rest of the board schematics will turn up along with a ROM image.