HP16C behavior on overflow when entering numbers?

[billf]

(07-29-2023 02:37 AM)mfleming Wrote:  Confirmed on my 16C

Hi again,

Another question, if you don't mind. How does BSP behave in these cases? I think two tests would be sufficient here... In 8 bit 2's complement signed integer mode:

CLX 2 5 5 (display reads -1) BSP (what happens?)
CLX 1 2 0 7 (display reads 127) BSP (I'm guessing 12?)

I can think of two reasonable outcomes for 255: a) Display reads "1" (as if you had pressed 1 CHS), or b) display reads 0, that is, BSP becomes like CLX when the displayed value is modified from the keystrokes.

Right now, my simulator does a), but I have a sneaking suspicion that b) might be what the real calculator does. b) requires a flag indicating an unsigned->signed conversion, but that flag is needed anyway to get the other observed behaviors.