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Question-is synthetic programming available for only for the 41 Series?


Yes, it's peculiar to that model and its variants.
The technique depends on a command sequence that allows you to delete code bytes between successive instructions, causing the resulting concatenation of byte codes to form instruction codes that aren't programmable via the keyboard.

There was something on the 67/97 that was called "synthetic programming" -- here is an old discussion on the topic.

Synthetic programming on the HP41 was so called because instructions unavailable from the normal keyboard were put together from pieces of standard instructions. (I suppose it could also have been called "analytic programming," since you have to bust the instructions apart first.) As far as I know, the 41 is the only HP calc that hack was possible with.



Some synthetic programming was also possible on the TI-58/58c/59, but wasn't as useful.

Where find info about synthetic programming on the TI-58/58c/59?

You'll find some articles here:



Extra memories on TI 58C

and things like the TI-59 fast mode, described in several other articles.

Fast Mode

Making the TI-57 have continuous memory

Fast Mode plotting program by Robert Prins

There was even synthetic programming for the TI-55! It was published in PPC Calculator Journal, Vol. 9 #6 and Vol. 10 #4. I believe this journal was edited by Palmer Hanson whose name I have seen in this forum.

Where find info about synthetic programming on the TI-58/58c/59?
There are a couple of pages about it, specifically accessing the HIR registers, at the end of the "book" (if you can call it that-- it's about 5/8" thick and stapled only in the corner) called "User Survival Guide for TI-58/59 Master Library" which I bought from EduCalc. It's by Fred Fish, who, at the time of printing (probably just photocopying or mimeographing), had a Tempe AZ address.

There was a Fred Fish in Arizona who compiled the largest collection of Amiga freeware ever seen. This was in '85, going forward for at least 10 years.


Garth, would it be asking too much for a scan of this paper? The TI-59 replaced my SR-56 back in the seventies. (I had some money left after I had parted with my girl friend at the time.) It did a good job during my time in University of Bonn. (I have a math degree.)

Marcus, saying "Bitte, bitte, bitte!"


It is available for download on Viktor Toth's website: here.

and more specifically an overview of the HIR intruction can be found HIR. (I mean "here" :-)



Merci, Etienne! I should have checked my TI docs folder more thoroughly. The document was already on my disk, but deeply buried between all these graphic calculator guide books. Shame on me!

Thanks all for help!!!