WP31s error recovery

[Dieter]

I just discovered that the 31s behaves differently from other HPs or the WP34s after an error occured. Example: type 3 [ENTER] -4 [LN] and you'll get the expected "Domain Error". Usually pressing backspace clears the error message and returns to the previously entered –4. The 31s however has lost this value and shows the 3 that was previously in Y. In fact, now both X and Y (!) hold this value.

I thought that the UNDO feature may help here, but pressing UNDO after the error occured does not recover the –4 either. Neither on the emulator nor on real hardware.

Is this the intended behaviour? Sorry if this has been discussed earlier, in this case a pointer to the respective thread will do. ;-)

Dieter