exxos's Atari, Amiga & retro forum

I know you can use 41256 chips as replacements for 4164s, so it might be worth a look at those. And I have some I can send you a few to try?

stephen_usher wrote: 18 Mar 2021 12:37
Just a thought. There are quite a few SMD 16bit DRAM chips available at lowish prices. Use one of those and just not use the upper 8 bits? I guess that they're bigger than a single 41464. Also 3.3V, which means more circuitry.

e.g. https://uk.farnell.com/integrated-silic ... dp/2901170

It is an option id thought about. I might use the same stuff off the TF328 and see how it looks.

PhilC wrote: 18 Mar 2021 13:13 I know you can use 41256 chips as replacements for 4164s, so it might be worth a look at those. And I have some I can send you a few to try?

Unfortunately those are 1 bits. I'm looking for wiiiiiiiiiider. :) 41464 is still looking the best option.

This is just for the Video RAM. Main system ram will be 10ns STATIC RAM.

PhilC wrote: 18 Mar 2021 13:13 I know you can use 41256 chips as replacements for 4164s, so it might be worth a look at those. And I have some I can send you a few to try?

He wants a single 8 bit wide chip, rather than 8 1 bit ones. This is the problem. :-)

terriblefire wrote: 18 Mar 2021 13:35

PhilC wrote: 18 Mar 2021 13:13 I know you can use 41256 chips as replacements for 4164s, so it might be worth a look at those. And I have some I can send you a few to try?

Unfortunately those are 1 bits. I'm looking for wiiiiiiiiiider. :) 41464 is still looking the best option.

This is just for the Video RAM. Main system ram will be 10ns STATIC RAM.

Just dual-port some of the SRAM and then you can be hacky and write directly into the video memory rather than having to push the data through the VDP. ;-)

ach for first version i'll leave the 41464s in ...

terriblefire wrote: 18 Mar 2021 14:43 ach for first version i'll leave the 41464s in ...

I'll have a look what I have as I have far too much NOS old ram.

So far I've found 12 x Mitsubishi M5M4464P which are 65536 x 4 bit, the same as the 41464, not sure if they aren't a little slow at 120ns.

Yeah I have too much ram, if its 4bit then it might be possible to use P21014? 256k x 4 bit. Got a few different variations and brands of similar chips and found my stash of 41464 chips.