Re: Mk14 vdu
Certainly useful to have that information, although I find it hard to imagine anyone putting all of those components onto a daughter board which then plugs into the CG IC socket. Regarding the use of an EPROM to substitute for the original PROM, this is one of the rare cases where that might not work because of the high access speeds involved. Even by modern standards, Bipolar PROMs are still very fast compared to EPROMs.
Karen could probably replicate the whole SOC VDU with a single PIC chip if asked nicely. Direct video output from PICs is something of a speciality for her.
I've often wondered whether, when you're starting with no VDU, it might be better to recreate the PE (Practical Electronics) VDU for the MK14. I never studied it in detail because I already had the official SOC item but by all accounts the PE one was better thought out. I think, though I'm not sure, that it had its own onboard RAM.
Tim posted link after link to MK14 related items in magazines in old British electronics magazines hosted on the americanradiohistory website, I'm sure one of those will be pointing straight at the PE VDU article(s).
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