> Dos it meant that when they were made, the component could be ordered > With CS1/CS2 in place of PB5/PB6 ? Yes. When you ordered a 6530 you specified what connection you wanted for the chip selects: for the ROM, it's an AND of any combination of the three chip select signals or their complements; for the RAM and the I/O each, it is an AND of any combination of the three chip selects and A6..A9, or their complements. If you do not use CS1/CS2 for addressing, you can use PB5/PB6 as normal port pins; similarly for IRQ vs. PB7. > Are the 6530-xxx all pin compatible, or is there multiple versions > according to the –xxx ? The -xxx specifies the ROM contents, and the other mask options too I suppose. They are pin-compatible, with the caveat that some use the high PB pins for chip select, and some do not. There is also an option of removing the pull-up on PB7; there might be more. Segher Message was sent through the cbm-hackers mailing listReceived on 2013-05-05 15:00:03
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