[Coco] [Color Computer] Re: POKE 65495,0
jdiffendaffer at yahoo.com
Mon Feb 5 10:48:16 EST 2007
>> Could it even be that different production runs of the SAM have
>> different behaviors?
>There was a second generation of the SAM chip called 74LS785 that I
>think appeared in the
>Coco2. One of its main features was to extend the refresh counter from
>7 bits to 8 bits. This
>allowed the usage of 64Kx1 dram chips. Since I don't have a spec sheet
>on the 74LS785, so
>I can't verify that any other functions have changed. From what I have
>read the 74LS785 is
>pin for pin compatible with the 74LS783/MC6883.
Actually, I think the newer SAM included a built in latch to reduce
the motherboard parts count. I don't think the pinout would change
much but it would function differently.
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