HP-65 Synthetic Programming??


Hello, all:

I received my set of MoHPC CDs a couple of days ago, and am having fun reading the manuals for old calculators I never had.

Just browsing the HP-65 manual, for example, I came across something really weird on page 27: The sequence of keys [STO][.] and [RCL][.]. Here's what the manual says:

"Clearing Unwanted Prefix

"[f][PREFIX] cancels the effect of a prefix so that a non-prefix operation can be done.

{yadda, yadda, yadda}

"The above procedure can also be used to clear these additional keys: [STO], [RCL], [DSP], [GTO], [LBL], [STO][.], [RCL][.]."

I'm sure this must be a typo. I've never heard of this key sequence anywhere (except on the HP-41; was the writer of the HP-65 manual having a premonition of things to come?). Just the same, I'd like to have confirmation from any of you HP-65 owners out there. The manual doesn't mention either of these key sequences ever again, nor is it in the index.

Any idea what the manual should read instead? The paragraph I snipped already mentions [f], [f-1] and [g], so it can't be that.

Ernie Malaga


Just a guess:May it have to do with storage and recall arithmetic? I mean STO+, STO-, STO*, STO/ and RCL+, RCL-, RCL*, RCL/. If so, the "dot" should be replaced by "any arithmetic operator".

As I don´t have a HP65, I only can imagine this, without any support.


Looking at my manual on page 27, it says:

1. Press STO.

2. Press a number key 1 through 9 to specify in which of the nine . . . to be stored.


1. Press RCL.

2. Press a number key 1 through 9 to specify in which of the nine . . . to be recalled from.

The "dot" after STO and RCL simply is a period representing the end of the sentence. If they had meant it to be a key stroke it would have used their standard format of having the appropriately colored little box around it.

As far as clearing the STO, RCL, GTO, LBL, and DSP prefixes, Warren is correct. It just terminates the above initiated sequences with the sole effect being that the number is terminated (it reformats the number to your set format, i.e. 0.00) and enables the stack lift.



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

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

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