520 STFM 256kx4 DIL to 1Mx4 SOJ

Upgrade your RAM from ST to Falcon.
gman
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Re: 520 STFM 256kx4 DIL to 1Mx4 SOJ

Post by gman »

exxos wrote: Thu Aug 01, 2019 12:23 pm
gman wrote: Thu Aug 01, 2019 12:19 pm 1: what's the resistor on the cable "manually connect A9 (pin 5) to the unused MMU pin 64."?
When you upgrade the RAM from say 1MB to 4MB you need a extra address wire, which is what A9 is. Basically without it, your new chips would be "stuck" with 1MB for example.
Thanks for the reply, Did I miss read your store page and you don't sell a 4MB RAM kit for this board?
This is pretty good info here, but having the correct parts and a more detailed guide would be great!
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Re: 520 STFM 256kx4 DIL to 1Mx4 SOJ

Post by exxos »

gman wrote: Fri Aug 02, 2019 1:15 am Thanks for the reply, Did I miss read your store page and you don't sell a 4MB RAM kit for this board?
This is pretty good info here, but having the correct parts and a more detailed guide would be great!
I do not do a kit for 4MB kit for that board no.
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
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