68kMLA Classic Interface

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Replacing a keyboard by an ADB hack

Posted by: bibilit on 2020-09-02 19:31:32 Hi, trying to figured out how to get rid of the keyboard to boot some units.  The Colour Classic for instance will only boot using the reset switch.  For testing purposes something less bulky will be fine, and apparently shorting pin 2 and 4 should work on any adb item or cable.  Anyone here has done that thing ?  I have been trying to poke around my keyboard and the switch to get the short (using a multimeter) but can’t see any.  Probably a diode in between.

Posted by: bibilit on 2020-09-03 18:21:24 Information online was misleading.  http://www.interfacebus.com/ADB_Pinout.html pinout was wrong on one of the drawings, so basically the correct pinout is the bottom one, and now using the switch pin 2 and 4 goes somewhere.

Posted by: quorten on 2020-09-05 11:17:34 Interesting, is plugging in only a mouse not enough to allow a computer to boot?

Posted by: bibilit on 2020-09-06 02:18:41 No, no way to short those two pins with a mouse only... without a hack.

Posted by: bibilit on 2020-10-10 16:43:08 So was able to find time to do the job.  I modified a suitable cable with a switch and had a try while testing a board fitted with new caps.  Works fine and no need to have a keyboard anymore.  By the way, had to remove and reflow the Egret chip to get it going (can’t remember last time It was not mandatory)

Posted by: olePigeon on 2020-10-11 06:42:05 @bibilit Would be cool if you could mount the switch behind the little Apple, and push the Apple to turn it on. 🙂

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