Re: RAM replacements

From: Gerrit Heitsch <gerrit_at_laosinh.s.bawue.de>
Date: Wed, 12 Sep 2012 20:24:56 +0200
Message-ID: <5050D378.1080409@laosinh.s.bawue.de>
On 09/12/2012 08:14 PM, silverdr@wfmh.org.pl wrote:
>
> And then using the second half for colour RAM replacment will be as easy as ORing it with _CS for 4114, routing 4114's _CS to SRAMs A16 and ORing R/_W?

No, the color RAM needs to be replaced seperatly due to the way it's 
hooked up the VIC (D8 - D11). That means it's read in parallel with the 
other RAM. You can either find another 2114 or LC3514A (still easy 
enough to get) or use a 6116 (see C128 schematics for the general idea) 
or any other available SRAM that's at least 4 Bit wide and 1K deep. Just 
tie all unused address lines to GND and the unused data lines (D4 to D7) 
to +5V using resistors (they used 3.3KOhm in the C128).


  Gerrit


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