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kellys_eye · 17th Aug 2018, 6:46 pm

I have an interface card (drives external machinery) that has a fault. The board manufacturers are no longer around and the chips (all DIP devices) have had their markings sandpapered off (grrr...).

I'm trying to identify the main controller device in a 64-pin Shrink DIP package where the only pins I can (so far) confirm are +5V on pin 43 and ground on pin 26.

When first checking the pinouts I thought I'd 'got it' when I identified data bus connections that matched up to the TMS9900 pinout but when I checked the datasheet the power pins were now where near what I've found....

I've tried the usual suspects (TMS9900, 68000 etc) but no results yet. It may even be a PIC-type device (??) but that's just me guessing....

Can anyone suggest types of device (in a 64-pin shrink DIP) that I could look up to see if I can find a match?

17th Aug 2018, 6:46 pm	#1
kellys_eye Octode Join Date: Jan 2014 Location: Oban, Scotland, UK. Posts: 1,129	Interface card on 486 processor I have an interface card (drives external machinery) that has a fault. The board manufacturers are no longer around and the chips (all DIP devices) have had their markings sandpapered off (grrr...). I'm trying to identify the main controller device in a 64-pin Shrink DIP package where the only pins I can (so far) confirm are +5V on pin 43 and ground on pin 26. When first checking the pinouts I thought I'd 'got it' when I identified data bus connections that matched up to the TMS9900 pinout but when I checked the datasheet the power pins were now where near what I've found.... I've tried the usual suspects (TMS9900, 68000 etc) but no results yet. It may even be a PIC-type device (??) but that's just me guessing.... Can anyone suggest types of device (in a 64-pin shrink DIP) that I could look up to see if I can find a match?