68kMLA Classic Interface

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Cable Driver/Line Driver/Buffer IC Suggestions please. ;-)

Posted by: Trash80toHP_Mini on 2016-12-18 18:36:15 TIA gang. First, I'd like advice on whether I need one or not for this little project. And what might be recommended. I decided it would be fun to hot glue a 2x9 strip of headers in between a pair of NuBus Slots. That way I could play switcharoo with the constant value high and low signals by making connections over a pair of eight inch M-F or F-F strippable rainbow jumper wires/IDC cables I conveniently have on hand. Figured this NuBus Slot ID signal playground might be a bit much without a cable driver IC to keep things on the level. I've got a half inch of clearance so DIP fits the first pass at feasibility checking for a .48" wide PCB. Perf board will probably work fine, but it's not very pretty in Illustrator. SMT isn't out of the question either, a single chip project sounds good! OK, here's the visual aid that deciphering my .TXT usually requires: :🙂 p.s. is epoxy or hot glue a better choice in terms of insulation when I stabilize mangled legs on wire wrap EuroDin connectors?

Posted by: Trash80toHP_Mini on 2016-12-19 16:15:22 I'm wondering if I'm overthinking this or falling back on my standby ID10T state? Here's the simplest diagram of the simplest form of what I'm trying to do. The low state appears to be a simple connection to groundIf so, no problem, but I'd really appreciate some help on the advisability of running four High State signals from a single High State signal tap. To chip or not to chip, that is the question  .  .  .  along with what KIND of chip might suit this application best? Addendum: might I be better off just using ground for low and a pullup resistor for high without ever even tapping the IIsi's signals at all?

Posted by: techfury90 on 2016-12-31 17:20:24 Yes. You don't really need a buffer for this because the signals will be a static state, if you will. I would suggest using ground for low and a pull-up for high.

Posted by: Trash80toHP_Mini on 2016-12-31 19:35:06 THX, figured that one out  .  .  .  finally! :🙂 I'm pulling high and low off two pins located very conveniently that plug directly into the IIsi's NuBus Slot and hooking them up to the rails on a jumper block PCB. That way I can play games with the Slot IDs of the adapter in my IIcx. See this post in TWO SLOT IIsi Nubus Card hack . . . Take 2

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