HP 12C ATSAM4L version: ON-f-ENTER

[brouhaha]

(03-06-2023 03:38 PM)rprosperi Wrote:  This was found and reported by (of course) Joe Horn last year.

I'm not at all surprised.

Quote:Note that it also disables the auto-power-off feature after some number of minutes.

I suspected that it might. I didn't leave it on to find out, because I thought it might also have increased power consumption compared to normal mode, though I haven't tried to determine whether that is the case.

Quote:To re-enable the ON key, press and hold f+ENTER then press ON.

That seems to behave in an inconsistent manner on my unit. I've seen:

1) does nothing, calculator still in forced-on mode
2) calculator turns off, and at the next power-on, gets "Pr Error" (memory lost)
3) calculator turns off, then calculator won't turn on for a while, or perhaps some number of repeated attempts
4) calculator turns off, then ON key turns it on normally

I assume that #4 is the intended behavior, but in my experience that's the least common outcome.

Quote:There's no info if this was done on purpose (e.g. for diags or battery life testing, etc.) or if it was a simple bug.

It seems highly unlike that it's a just a bug.

Quote:The fact that the mode can be both enabled and disabled suggests it was there for some purpose, but there were other deleterious side-effects noted (some functions performed more slowly)

Interesting! I didn't poke at it enough to discover that.

Quote:so probably best to NOT use this "feature".

Agreed. It's clearly not intended for users.