Newsgroups: comp.sys.apple2.comm Path: blue.weeg.uiowa.edu!news.uiowa.edu!hobbes.physics.uiowa.edu!math.ohio-state.edu!howland.reston.ans.net!wupost!waikato!comp.vuw.ac.nz!actrix.gen.nz!dempson From: dempson@actrix.gen.nz (David Empson) Subject: Re: How to replace the "triangle chip" on Apple Super Serial Card? Message-ID: Organization: Actrix Information Exchange References: <36ut57$ruk@news1.digex.net> Date: Thu, 6 Oct 1994 11:30:38 GMT Lines: 47 In article , David C.W. Chiu wrote: > In article <36ut57$ruk@news1.digex.net>, > Christoph Berendes wrote: > > >I'd rather not replace the whole Super Serial card. Anyone have any leads > >on where I might find just that little chip? I suspect it's apple > >proprietary, and a first round of phone calls to local repair shops > >supports this. > > That isn't a chip, but a jumper block. I no longer recall the internal > wiring, but you can probably figure it out using a multimeter... Or look at the original (Apple II+ generation) manual for the card, which has a full circuit diagram, and shows the internal wiring of the jumper block. It is a 16-pin jumper block, wired as follows: 1 --\ /-- 16 | | 2 --/ \-- 15 3 --\ /-- 14 | | 4 --/ \-- 13 5 ------- 12 6 ------- 11 7 ------- 10 8 ------- 9 i.e. 1-2, 3-4, 13-14, 15-16, 5-12, 6-11, 7-10, 8-9. The arrow points to the right side (pins 9-16) in the above diagram. With the jumper block inserted into the card and the arrow pointing to MODEM (up), the card is in its "standard" configuration, with pin 1 in the lower left corner. -- David Empson dempson@actrix.gen.nz Snail mail: P.O. Box 27-103, Wellington, New Zealand