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Are Lisa 2/10 and 2/5 I/O boards interchangeable

Posted by: max1227 on 2020-04-28 16:04:16 Hi Lisa enthusiasts, I have a 2/5 which has I/O problems due to the corrosion and myself and a fellow member are trying to diagnose. I need to find out if the I/O board is the fault or potentially the edge connectors or traces on the motherboard. I don’t have a spare I/O board unfortunately.   Is it possible to interchange a 2/10 I/O board for a 2/5? This will require use of the same 2/5 motherboard, CPU card and memory boards although the latter 2 I believe are interchangeable between any Lisa system ROMs dependant I suppose if you have the Mac XL screen mod and 800k drive. A source using the Lisa FAQ says it is but the Lite Adapter should see modifications which involve cutting traces. So if I disconnect the Lite Adapter can I do it? Has anybody tried this? Ive also read many posts on this forum that say you will destroy or damage the system if you plug in a 2/10 I/O board into a 2/5 system and since the rarity of these boards are forever increasing I would like very much to not add another dead one to the pile.    Max

Posted by: compu_85 on 2020-05-26 08:31:49 You don't even have to disconnect the Lite adapter, the floppy drive simply won't work. The Lite adapter does 2 things: a pin converter to hook up the sony, and a PWM converter for the disk speed signal which is different between the twiggy and sony disks. -J

Posted by: sunder on 2020-11-20 07:59:23 So I haven't tried this yet, but vintagemicros has an altered LisaLite adapter here: https://www.ebay.com/itm/Apple-Lisa-Lite-Card-Modified-to-Allow-a-2-10-I-O-Bd-to-be-Used-in-a-Lisa-2-5/143173144110 which says it will allow this to work. You can see the modifications are made by two bodge wires:

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