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Old 4th Sep 2020, 11:38 pm   #16
Buzby123
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Join Date: Oct 2011
Location: Culcheth, Cheshire, UK.
Posts: 637
Default Re: I found it !. A very sorry looking MK14

I've unplugged the daughter board, just to see it a bit better.

It looks like my Micky needs this board to run. IC16 on the main board has been removed, and some pins on two of the 2111s have been bent up and wired to the daughter board. I think there is a lot of address decoding which is now on the daughter board.

Also, there are two 74S571 chips on this board, and two still on the main board.

It's coming back to me through the mists of time, I think the toggle switch near the red button would let me select 'old' or 'new' ROMs. ( Don't ask me why I thought this was a good idea, it was a long time ago. )

This is one seriously hacked MK14, I must have been really enthused to have put so much effort into it.

One thing I am missing is documentation. ( I might find it, but I'm not holding my breath. )

Does anyone have a link to an Issue 2 schematic ?.

Cheers,

Buzby
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