Does anyone recognize this Lowercase Character Generator ROM?

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Does anyone recognize this Lowercase Character Generator ROM?

I recently came into possession of a very well kept 1981 Rev 820-0044-01 Apple ][ Plus.
It was purchased in 1981 by a woman in her then late Forties, now late Seventies.
She used it for her accounting business in Mesa, AZ. Definitely, she was not a Hobbyist/Hacker.
Anyway, I came to discover that it had a non-standard ROM installed in the ROM SPCL socket on the Motherboard.
The only descriptive info on the chip was a sticker labeled "© Copyright 1980 MICROTECHNICAL SERVICES"
I couldn't find anything online about this Character Generator ROM nor the company which produced it.
There is no Lowercase Mod done between the Keyboard Encoder and the Motherboard.
Interestingly, on screen it generates the same character set as an Apple //e except for ascii (127) which produces a solid Apple icon instead of the square block.
I think the lowercase characters can be invoked in certain programs using the Escape Key as the Shift Key.

I would greatly appreciate any information about this chip and its usage.

mmphosis's picture
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Re: Does anyone recognize this Lowercase Character Generator ...

Interestingly, on screen it generates the same character set as an Apple //e except for ascii (127) which produces a solid Apple icon instead of the square block.

The descenders probably do not descend like on the Apple IIe, and I am guessig that there is no MouseText.

There is another range of characters that might be of interest: $80 to $AF (128 to 159)

To display these on the screen from Applesoft BASIC, type the following line and press return...

HOME :A = 1024: FOR I = 128 TO 159: POKE A,I:A = A + 1: NEXT

On the Apple II, these "control" characters are simply a copy of "@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_", but they might appear differently with a custom ROM character set.

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Re: Does anyone recognize this Lowercase Character Generator ...

It may be one of the custom character ROMs distributed in Great Britain.....
there where several comapanies that offered "lower case chararcter ROMs" for the II and IIe models,,,
the advantage was to get the ability to use lower case in wordproceeors like Apple Writer II and similar
without installing a "lower case mod". Such offers "invaded" the USA from Canada by Users moving from Great Britain to Canada
speedyG

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