Hello Jim, > I have been asked to run a modifed 2364 adapter that allows pin 20 to > be inverted on non-inverted. I used a hct86 with a jumper to ground > on one side of the gate to alter the inversion of the line. Okay, the 2364 has one chip select signal. So you have two states: inverted or not. > It looks > like there might be value in supporting a 2332 with a similar setup. 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. > The 6540 adapter I have uses a hct138 to support all of the select > lines. 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! Greetings Martin Message was sent through the cbm-hackers mailing listReceived on 2011-08-11 14:00:08
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