WP 34S bitwise logical operations bug?

I'm running build 2356 on my (ex-!)HP-30b. When I do yellow-shift-+/- (i.e., entering binary mode), "2c64" appears on the top line and "b" appears in the exponent. So far, so good.

Now, I enter 1010 and press ENTER, twice. I then do green-shift-7 - i.e., AND. I get a binary integer with 64 1s in it! I had expected to get 1010.

Digging out my HP-20b, still running a late version 2 build, I find that I do get 1010 as the result.

A little more experimentation reveals that in version 3, 0 AND 0 is 1 (other arguments giving correct answers). OR has the same problem, and XOR doesn't work either!

Is this a bug? Or have I inadvertently selected some special "give wrong answers" mode setting?

Nigel (UK)


Bad bug :-(

I have no idea where this crept in. I'm not aware of having changed anything in this area except the register access (which might well be the culprit.)

Edit: Fixed. It wasn't the register access. :-)

Edited: 3 Feb 2012, 6:36 p.m.


Was a bug. Fixed now and will be available in the next build.
Part of the flash recovery space saving measures gone awry.

- Pauli


I had just fixed it but my commit failed because of your fix. :-) It's built now.


Thanks for fixing this - and for the whole project, which continues to be amazing! I haven't enjoyed myself so much for years!

Nigel (UK)

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