Hi,
I have an analog synth (a paia fatman) which i think i fried the microprocessor for, and am looking for a replacement... the original chip was an intel 8031AH (made in 1980!) and i was wondering if any of the atmel processors are pin/code compatible... i am not really worried about memory size (as the code is stored in an EPROM), i just want to find the closest replacement for the chip...
any help would be MUCH appreciated...
bodhi
The AVRs are totally code incompatible with the 8031. Atmel does make some 8051 family processors that would work (such as the AT87F51), but you'll get no advantages from it, since you're using it as a straight drop-in replacement.
I have a massive collection of 8031's in my warehouse. If you're anywhere on the North American continent, I'll be happy to send you a couple, no charge. Just let me know where you want them mailed.
--John
Atmel's 89C51 (or 89C52) should work as a replacement.
--Dhananjay
Thank you both... John, i wish i could take you up on that offer but i live in australia :(
i am trying to source one locally, otherwise i might have to get one from Paia, the only reason i asked about the Atmel processors was because i read somewhere that they made 80x1 compatible chips...
I just read that dontronics has an 89C52 for sale... i might try that...
once again, thanks to both of you
bodhi
Just a thing to remember all of Atmels 8031 controllers have onboard memory these days. So you cannot use that part as a drop-in-replacement; at least I think so.
You have to use a 8031 without any onboard memory such as Philips, Infineon or Dallas Semiconductor.
Although most big 8031 have types that cater for OTP, Flash, EEPROM, EPROM or No-Memory.
Regards.
Arno.
Actually, on most you can, because of the EA# line. On an 8031 with no internal memory, you are required to pull the EA# line to ground for normal operation. For parts with internal memory, you pull this line high to use the internal memory, or low to use external.
Summarizing, most parts with internal memory can be treated as parts with no internal memory by pulling the EA# line low. In a design that used an 8031 with no internal memory, this line would be grounded by default.
--John
Hi John,
you are right. Any 8051 derivate with EA pin can be used as ROMless.
Also you can switch from internal to external and reverse. E.g. I use a bootloader inside the internal ROM and if the application was loaded into external RAM, I switched EA to GND and voila, the code on external RAM was executed.
Peter
i just thought i'd let you know that the 89C52 worked like a charm! i dropped it in, and my fatman now works perfectly! thanks, once again, for all of your help!
bodhi
