newRPL: [UPDATED April 27-2017] Firmware for testing available for download

[Claudio L.]

(01-22-2016 03:49 PM)Helix Wrote:  Just for information:
I've tried to install the last version of newRPL on my HP50g, and this time I've had a lot of difficulties.

After the traditional update and reset procedure, the screen displayed "exception data abort".
CONT, EXIT, shift WARMSTART and Shift RESET returned to the same screen.
OFF didn't work.
ON-A-F didn't work either.
Reset with a paperclip returned to the same screen.
Removing a battery didn't work, because as soon as the battery was inserted, the calculator still displayed the same screen.

I've tried to install previous versions of newRPL that was saved in my PC, and to my surprise they didn't work either, showing the same problem. Flashing the calculator with the original HP ROM worked perfectly, but flashing again with newRPL returned to the same problem, but with a different screen: "exception : corrupted MMU".

I've found a solution: pressing Shift RESET, and very very quickly pressing ON-A-F. It was quite challenging, but this time I could wipe the memory. Since the calculator seems to work normally with the last version of newRPL.

There was one update a couple updates ago that required full memory wipe, due to a serious low-level reorganization.
But I see your point: those low level exceptions should *always* offer to do a full memory wipe. I'll work on that.
However, next time you see a data abort, please either take a picture or write down the register contents and email it to me.
newRPL has object validity tests upon boot, so it shouldn't crash like that, ever. While crashing on invalid objects used to be normal on the 50g, it is not acceptable in newRPL.
The correct behavior is for the invalid object to be detected and replaced with the number 0 (for lack of better object) before newRPL starts.
The "corrupted MMU" message is a consequence of those thorough tests on boot. The RAM was overwritten by the stock ROM, with enough leftovers for newRPL to detect it was there before, but something wasn't right. That means the safety checks are working fine, but should give you the option of doing a full memory wipe too to correct the problem.