Regarding the Atari 800...
What's the difference between the 6502A and the 'Sally'? Is it simply a revision, or do the changes improve performance?
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Sign up to join this communityRegarding the Atari 800...
What's the difference between the 6502A and the 'Sally'? Is it simply a revision, or do the changes improve performance?
It seems the 6502C "Sally" added a HALT pin to allow Atari to remove four support chips and thereby build cost-reduced versions of the Atari 400 and 800.
PIN 35 on the SALLY used HALT. There were other advantages. The Wikipedia article is pretty thorough. HALT was used so the ANTIC/GTIA graphics chips could halt the 6502 easier since they shared the same bus.
The SALLY was used in the Atari XL and XE 8-bit computer line, not to mention the 5200 SuperSystem and the 7800 ProSystem gaming consoles.