WP31s error recovery

[BarryMead]

(03-02-2015 07:34 PM)Dieter Wrote:  Barry, that's a very interesting observation. However I do not think this is the way the 31s should behave. It is an ultimately "classic" RPN device, and the documentation does not know of an input register as opposed to the usual stack register X. In the first example, the [ln] key computes the natural logarithm of X, so there must have been a –4 in X before. Likewise the [+] key adds Y and X, so again there must have been a 4 in X. And finally there is a LastX command (OK, RCL L in this case) that restores the X-value before the last operation.

So I do not think that the examples show the behaviour intended by the 31s team. Pauli? Walter?

Dieter

I agree. One would naturally tend to think that the input register and the X register are the same thing. The fact that they are different is a convenience to the developers, not the user. I applied Bit's patch and it does seem to fix the error recovery and UNDO behaviors for both of your examples. Thank You Bit! Dieter: If you would like to try out Bit's patch unzip and flash your WP-31s with this file, Barry (See a later posting in this thread for a more updated wp31s flash image with Bit's Better Undo feature).