WP31s error recovery

[BarryMead]

(03-05-2015 09:39 PM)rprosperi Wrote:  

(03-05-2015 08:29 PM)BarryMead Wrote:  Bob: I just flashed one of my wp34s calculators with the NEW wp31s.bin image and the UNDO of UNDO works as expected.
I do get 1,1,2,12 back in the registers after the 2nd UNDO using your example. I suspect that you flashed your calc with the
OLDER wp31s.bin image. This seems to be true, because when I just checked the "Download Count" only 1 person had downloaded
this latest file, and that was me to verify that it contained the latest version. Download, unzip, and flash your calc again with the latest
version and the UNDO of UNDO will work.

Barry: I didn't flash anything, I was just aswering Dieter's inquiry about what Undo of Undo should do.

A multi-step undo would be lovely of course, but not feasible for these memory-constrained machines.

The Undo of Undo back to just prior staet (flipping back and forth as it were) is, IMHO, the best solution as it's utterly consistent with the definiton of Undo and it gets you back to the stack you really may have wanted when you hit Undo the first time (something many Undos don't do).

BTW: Thanks for jumping all the way in and becoming another 31S/34S contributor! Like Pascal, Sanjeev, Jonathan and Bit before you, it lets more stuff get done without necessarily having to add work for Pauli or Marcus, plus adds some new eyes, ears and ideas from folks that can actually see and understand the code.
Edit to add thx.

It seems to work very well, and on the Qt Emulator version you can even exit the program, restart it, then press UNDO, and it will still toggle between the last two states. This is because Bit included an UNDO memory save/restore feature in his patches of the Qt emulator.
About "Jumping In", When you are having fun playing with toys like the WP-34S it doesn't seem like work. It just seems like a fun challenge to keep one's mind sharp. Once Bit helped me get my Linux based compiler working it was easy. I have contributed to hundreds
of open source projects over the years. Since I "USE" open source programs, like Linux, it just seems fair that I "GIVE BACK" to the open source community where I can.