VOGONS

286 jumper setting

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First post, by Kouwes

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I bought a 286 with a Headland HT12/A board and an interesting CPU from Siemens.
Anyway, it came with 1MB onboard RAM and a leaky battery that caused a bit of corrosion but did no damage at all.
So I removed the battery, added 4 x 1 MB and also an Intel 80287-10 FPU.
I‘m not sure about the jumpers (there are 2 near the FPU) and I couldn’t find any info. Is anyone here familiar with this board?

Of course I could just give it a try but I‘m waiting for a 3xAA battery holder I ordered 🙂.

Reply 1 of 2, by vstrakh

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Looks quite similar to this one: https://theretroweb.com/motherboards/s/tidalp … i-025c-ht12-286
The JP2 is likely selecting the FPU frequency divider. You can validate the assumption by checking continuity between JP2 pin 2 (the middle one) and the FPU socket pin 39.

Reply 2 of 2, by Kouwes

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It appears your assumption is correct: there is continuity.

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