On 8/11/2011 8:26 AM, Hoffmann-Vetter, Martin wrote: > Okay, the 2364 has one chip select signal. So you have two states: inverted > or not. That's the first part. Yes, it is optionally inverted to handle 2364 variants with CS instead of /CS > Yes, but the 2332 has two chip select signals (see the datasheet > http://www.classiccmp.org/cini/pdf/Commodore/ds_2332.pdf or > http://archive.6502.org/datasheets/synertek_1981_1982_data_catalog.pdf at > page 2-17). You can programm it via mask, so any combination are possible > (0: low aktiv, 1: high aktiv and 2: don't care). You can use both, only one > or non chip select. And all used chip select can be inverted or not. I accomplished this by using the /CE signal on the EPROM. Both CS signals are routed to '86 units to optionally invert them, and then one is routed to EPROM /CE while the other is routed to /OE > Or you use a 139 (open collector) with a pullup resistor. Now you can put > one or more jumper and have a programmable wired or gate! Can you clarify? I understand '129 is not the IC, but even with a suitable IC, what are the instances where you would *NOT* want the decoding of all the CS lines on the 6540? Message was sent through the cbm-hackers mailing listReceived on 2011-08-12 03:00:03
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