HP-65 synthetic programming


I recently got a HP-65 and quite a few of its application pacs. Also a few programs on magnetic cards from the previous owner. I ran one card and the calculator behaves in ways that are not documented anywhere, that I can tell. Like putting multiple decimal points in the display, and spaces, and displaying an updated timer.

So I searched Google for hp65 synthetic programming, and this thread from 2001 came up:

There were a lot of undocumented logic functions in the 65.

The PPC club published them there is even 3 way conditional jumps.

Does anyone know anything about this capability on the HP-65?


You *really* want the PPC CD-ROMs with the scans of the PPC Journal (and before that, 65 Notes). Jake Schwartz has scanned them all. You just need PPC CD1 for the 65-related material.

The short answer, though, is that IMHO the vast majority of the synthetic programming for the 65 was only amusing and not very practical. Not like the 41, where synthetic programming greatly expanded the capability of the machine. (Though later ROMs from HP and 3rd parties reduced the need for 41 synthetic programming somewhat.)


Thanks Eric. I ordered the CD from Jake tonight.


Hi Don,

The CDs are on the way.

Jake Schwartz


Thanks Jake.


I received an HP 65 a while ago, but the cards with it were from an HP 67 (I'm pretty sure, but I'm not at home so I can verify) ... running these thru the 65 gave the results you have.


A while back I posted a question if anyone had synthetic programming mag cards for the HP-67. I got one answer from a guy who said he would be happy to ship me a set, but I never heard any more from him. Anyone has a copy of such cards?

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