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Old 13th Mar 2021, 5:59 pm   #34
ortek_service
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Join Date: May 2018
Location: Northampton, Northamptonshire, UK.
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Default Re: The Transam Triton Personal Computer

My (a bit old now) Dataman 48XP can also do the National Semi DM54/74S287 and DM54/74S472.

I can also usually do Tesla MH74S287's (but no other makes 74S472's) on a later (& different Elnec-designed) Dataman 48Pro-series, when I can access it again.

Although there may also be some other, different-numbered, equivalents, here:
https://www.mikesarcade.com/cgi-bin/...ge=PromRef.txt that these programmers will do.


You may also be able to substitute an EPROM / Parallel EEPROM (You can these down to 45ns, although mainly larger / more modern CMOS types, and often quite cheap - as little as 50p for W27C512, (actually an EEPROM))
for these - like has often been done with C64's unreliable custom PLA (Although it does mean converting logic equations into an all-combinations lookup table and some pin-adapters)
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