The GEOS/Berkeley Softworks supplied an "IRQ Manager" card for the Apple IIe that did not have a mouse card. I have two of these cards. They only have two chips on them: SN74LS161AN and SN74LS03N The first made by TI the second by Motorola. There are also three resisters. The card was to be put into slot 7, and it only had two fingers on the right side, and four on the left. GEOS had to have have this to run on a IIe. I hope this helps some. Roy -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 80,000 Newsgroups - 16 Different Servers! =----- Exegete (millers@noneofyourbusiness.com) writes: > The GEOS/Berkeley Softworks supplied an "IRQ Manager" card for the Apple > IIe that did not have a mouse card. I have two of these cards. They only > have two chips on them: > > SN74LS161AN > A 4-bit synchronous binary counter. This would seem to be the datasheet: http://www.ee.washington.edu/stores/DataSheets/74ls/74ls161.pdf though I did not take the time to look at it. A simple pinout is here http://www.xs4all.nl/~ganswijk/chipdir/pinusr/74161.txt > and > > SN74LS03N > Quad 2-input nand gate with open collector output. The fact that this has an open collector is a big hint that it connects to the interrupt line. Again, a likely datasheet is this: http://www.ee.washington.edu/stores/DataSheets/74ls/74ls03.pdf One might guess from context, that the counters are cascaded, and are fed from a clock signal on the Apple bus, providing an interrupt, via the 74LS03, to the interrupt line. Michael