4264 vs. 2164 RAM chips
- Zippy Zapp
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Re: 4264 vs. 2164 RAM chips
Ok cool. Beyond the VSP fix there are not other compatibility problems by the switch? Sounds like a good idea.
Commodore - Changing the world 8 bits at a time.
Re: 4264 vs. 2164 RAM chips
Hi Gyro Gearloose,
I was doing some research online on RAM chip identifying numbers and Google brought this thread up.
If I read you right I need to run a jumper wire from pin 1 across the top of the chip on to the GND pin 16 of the KM41C256P RAM chip. Then would I insert the chip as normal into a RAM socket with no lifting of the RAM legs?
I was doing some research online on RAM chip identifying numbers and Google brought this thread up.
I actually have a quantity of KM41C256P RAM chips. I'm willing to give this a go.Gyro Gearloose wrote: ↑Wed Jun 19, 2019 3:06 am Hmmm, forgive my intrusion upon this learned discussion, but I think you can just pop in a 41256 chip in lieu of a 4164 and it should work as a 64k chip. The C64 will simply never address the extra memory.
The extra A8 line on the 41256 would be left floating, so you'd need to tie it to a low-impedance logic level, just strap a wire across to pin 16.
Anyone ever try this?
If I read you right I need to run a jumper wire from pin 1 across the top of the chip on to the GND pin 16 of the KM41C256P RAM chip. Then would I insert the chip as normal into a RAM socket with no lifting of the RAM legs?
- Gyro Gearloose
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Re: 4264 vs. 2164 RAM chips
Yes. If you already have sockets and you know that the 41256 chip is good, should be a simple hack. You just need to try with one.
The price one pays for pursuing any profession, or calling, is an intimate knowledge of its ugly side.
Re: 4264 vs. 2164 RAM chips
Hi Gyro Gearloose,
Okay, good. Thank you for the information.
I'll get back to you.
Okay, good. Thank you for the information.
I'll get back to you.
Re: 4264 vs. 2164 RAM chips
Hi Gyro Gearloose,
Yes, I just tried several of them. I can say they work fine.
I am surprised they work considering the manner they were stored in for 30 odd years and how I was handling them recently.
I must say I didn't realize they were CMOS style until I started looking up datasheets.
I tried two chips and both worked fine.
Yes, I just tried several of them. I can say they work fine.
I am surprised they work considering the manner they were stored in for 30 odd years and how I was handling them recently.
I must say I didn't realize they were CMOS style until I started looking up datasheets.
I tried two chips and both worked fine.
- Gyro Gearloose
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Re: 4264 vs. 2164 RAM chips
There we go. Something positive in 2020 finally.
The price one pays for pursuing any profession, or calling, is an intimate knowledge of its ugly side.
Re: 4264 vs. 2164 RAM chips
Hi Gyro Gearloose,
Absolutely! I can't wait to put Covid19 behind us......
I was doing some online research related to tracking down some IC part numbers and found this interesting site talking about which 4164 64K x 1 DRAM chips worked in a Atari800XL from a stock C64 memory chips.
https://atariage.com/forums/topic/22716 ... computers/
Here's a few screenshots from this site with a table of suitable 4164 64K x 1 DRAM chips.....
Absolutely! I can't wait to put Covid19 behind us......
I was doing some online research related to tracking down some IC part numbers and found this interesting site talking about which 4164 64K x 1 DRAM chips worked in a Atari800XL from a stock C64 memory chips.
https://atariage.com/forums/topic/22716 ... computers/
Here's a few screenshots from this site with a table of suitable 4164 64K x 1 DRAM chips.....
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