Re: Mk14 vdu
As a matter of fact I do have four 100pF capacitors fitted, not three, and now four 56pF capacitors in parallel with them. (A8-A11). 4 x 100pF was better again than before but wasn't quite perfect, still occasional corruption of the 0Bxx block when writing to 03xx.
At the moment with 100+56pF on each of the four lines it appears absolutely solid, but I have no way of knowing whether that is only just enough capacitance to make it work reliably, so tomorrow I'm going to up it to 180pF each line to see if it:-
-Keeps working.
-Stops working.
Between us, Tim and I need to arrive at a minimum and maximum value for these capacitors which will hopefully guarantee operation of this circuit for anyone else who builds one.
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