WP34S derivative and solver reset  Printable Version + HP Forums (https://archived.hpcalc.org/museumforum) + Forum: HP Museum Forums (https://archived.hpcalc.org/museumforum/forum1.html) + Forum: Old HP Forum Archives (https://archived.hpcalc.org/museumforum/forum2.html) + Thread: WP34S derivative and solver reset (/thread215801.html) 
WP34S derivative and solver reset  Alessandro Castellani (Italy)  03282012 Hi,I want to evaluate the first derivative of this function on my wp34s: f(x)=(3xx^2)/(x4) and I wrote this program:
LBL A
LBL B
I enter , as initial estimates, 10 and 10 then SLV B as reply I read reset on display. Thanks in advance.
Alessandro
Re: WP34S derivative and solver reset  Paul Dale  03282012 I can reproduce a lock up here, although it isn't a reset. I suspect it might be related to nesting these functions not being quite right. Marcus will have to look into where the crash occurs I suspect. This was an addition to version 3 firmware that hasn't been exhaustively tested.
Re: WP34S derivative and solver reset  Marcus von Cube, Germany  03282012 Pauli, what firmware? There was an issue with the watch dog not resetting the device properly but locking it up instead. Alessandro's case makes me believe that the watch dog kicks in because it isn't serviced in time by the solver routine. I'll check it. Edit: I get a stack overflow even in the emulator :( Edit again: I can rule out the watch dog, it must be an access violation of sorts which happens during the SLVS step. Now it gets tricky to find out what happened. Edit again: I found an uninitialized variable in the solver, chances are rising that I can fix the bug.
Edited: 28 Mar 2012, 9:40 a.m.
Re: WP34S derivative and solver reset  solved (hopefully)  Marcus von Cube, Germany  03282012 Revision 2726 should fix this nasty bug. Dominic, this is something to be back ported to V2 because it seemed like an old one. Look for the changes in decn.c! I've updated the release ZIP file, too.
Edited: 28 Mar 2012, 10:33 a.m.
Re: WP34S derivative and solver reset  solved (hopefully)  Dominic Richens  03282012 Yes, it's time to update the V22 zip file  it has been four months and I think there are a few other bug fixes that you guys have submitted to the V22 branch since then.
Re: WP34S derivative and solver reset  solved (hopefully)  Marcus von Cube, Germany  03282012 You'll need to fix decn.c before you compile.
Edit: I've modified the source but you need to compile the stuff. Edited: 28 Mar 2012, 4:11 p.m.
Re: WP34S derivative and solver reset  solved (hopefully)  Dominic Richens  03292012 I build the current V2.2 source files and uploaded a zip file with calc.bin, calc_full.bin and the windows emulator updated. The version is "34S V2.2 2738"
I didn't do any extensive testing, just make sure the calc_full.bin would flash my HP20b, that VERS returned the expected alpha and that basic calculations worked. I didn't actually verify that any of the bugs that are supposedly fixed with this build are fixed. I'll leave that to some intrepid V2.2 user.
