[Coco] [Color Computer] Re: POKE 65495,0

[James Diffendaffer]

>> Could it even be that different production runs of the SAM have

>> different behaviors?

>>

>> JCE

>>

>

>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.

>

>james 


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.