Casio MX101 replacement for 4416 RAM?

بواسطة Argon

Paragon (1119)

13-02-2018, 12:42

Hey.

I have a Casio MX101 with defective RAM (one of the RAM DIPs gets too hot to touch).
However, I don't have any 4416 DIPs.

I saw this Commodore 16 mod where 4416 is replaced with 4464: http://myoldcomputer.nl/other-computers/commodore-16/commodo...

Would something similar also be possible with the MX101?

Any other suggestions?
Maybe someone has some 4416 for sale?

Thanks!

بواسطة jltursan

Prophet (2619)

13-02-2018, 20:06

Absolutely, you don't need anything special, they're drop-in replacements.

بواسطة Argon

Paragon (1119)

14-02-2018, 11:26

Okay, thank you

So if 4464 will work, then 41464 should also work, right?

Thanks.

بواسطة Nprod

Expert (99)

17-02-2018, 14:19

I'm in the middle of doing the same for a Sanyo machine that uses 4116s and there's some modification needed to make it work with 4164s. Are you sure they are 4416 instead of 4116s?

بواسطة Argon

Paragon (1119)

24-02-2018, 17:42

Yep, just double checked, mine has 2x 4416 + 2x 81416

بواسطة jltursan

Prophet (2619)

24-02-2018, 18:48

Quote:

So if 4464 will work, then 41464 should also work, right?

Sure!. Sorry for the late response...

بواسطة Wild_Penguin

Hero (644)

25-02-2018, 15:22

Where can you source these 4464 (or compatible) memory chips?

I mean, these are not made any more AFAIK. There are several "new old stock" sellers out there. I ordered some for my NMS8255 a way back from eBay (or was it Alibaba?), and actually was succesfull in the end. That was a small miracle even if you do not take my soldering skills in consideration, since clearly the 20 or so chips I got were not new old stock contrary to what the seller claimed, since few even had a small blob of sodler left over! I believe they are / were cannibilized from old electronics, cleaned carefully and sold as "new old stock" (and might pass as such, if you do not scrutinize them carefully, as I did). One of the chips I got was faulty (luckily I needed only 16, and the originals were also left as "extra").

In the thread I was trying to debug the mapper circuit (the instructions were faulty, btw) it was also suggested to use some more modern RAM chip and make the mapper from the scratch. Given what I learned from the procedure and the thread, I'd do the RAM addition with more modern chips since these old ones are difficult to come by, and there's a good chance they are faulty / used despite what is being claimed.

Just one last advice: replace the chips with sockets. Do not trust "new old stock" chips!

بواسطة mtn

Champion (265)

25-02-2018, 16:40

I bought 4464:s from Ali Express a while back, these were also advertised as NOS but they were most definately not, you could see that the legs were straightened and quite recently had a "reflow" of fresh solder, because they were so nice and shiny

However! They all worked 100%, Ive used them in the modifications of a Spectravideo 738 to MSX2(+) (which I could not have done without ROMs from NYRIKKI, thanks again!), and also in a SD-Snatcher cart (for 128 kb) and also in some other repairs. (Pinball machines)

I got them from "IC chip store" on aliexpress.