Re: Mk14 vdu
I've just had to remind myself: I'm not constrained to the way the hardware works: My PIC code can cache an entire row of character or graphics data to avoid repeatedly fetching it.
With 512 bytes containing the whole display data, and 256 scan lines over which to display it, the PIC only needs to perform two memory accesses per scan line!
I can make these very relaxed indeed, timing-wise.
How's about 1 microsecond between NRDS going low and sampling of data from bus?
That should cope with even the slowest memory of the era.
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