WP-34S: Little issue with program step indicator
#1

Hello,

I noticed a strange behavior with my WP-34s (3.2 3450):

Say, I do not have any program in RAM, then the indicator shows 527 steps available for programing in my calculator. After executing some chosen program in the library (TVM, MIO for example), the calculator shows 526 steps, so one step less. I tried some things:

- CLP does not change anything (still 526 instead of 527)

- Creating an instruction and deleting it gives back the missing step.

- CLPALL also returns to the 527 steps available.

- Some library instructions do not alter the step indicator, for example any vector routine: V.V or V+V, they both behave :-)

That is it. Just curious on why executing some programs in the library alters the program step indicator.

Thanks and regards,

Miguel.

#2

I believe that the memory available for program steps is shared with the memory used to create local memory variables. So if a library function makes use of local variables, that would decrease the reported "Free Steps" shown. This is mentioned on page 173 of the printed manual (or page 154 of the pdf version).

Edited: 5 Sept 2013, 3:15 p.m.

#3

Thank you Barry.

But how does that explain that creating and then deleting just one instruction, makes the indicator come back to normal? Deleting an instruction also clean the local variables?

Thanks,

Miguel

#4

I am pretty sure that deleting a program step clears the return stack which includes all local variables. If it didn't, all the return addresses would be incorrect after the delete. Marcus would know for sure.

- Pauli

#5

Thank you Pauli. I forgot about the return stack.

Regards,

Miguel

#6

I've yet to check what the exact reason is for the vanishing program step. The explanations so for seem correct. You can easily clear the return stack with the sequence g RTN from the keyboard. Check if this sequence "repairs" the free memory display.

#7

Hi Marcus,

Yes, It does indeed.

Thank you and regards.

Miguel



Possibly Related Threads…
Thread Author Replies Views Last Post
  [WP-34S] Unfortunate key damage with update to V3 :( svisvanatha 5 3,297 12-10-2013, 11:37 PM
Last Post: Les Bell
  WP-34S (Emulator Program Load/Save) Barry Mead 1 1,869 12-09-2013, 05:29 PM
Last Post: Marcus von Cube, Germany
  DIY HP 30b WP 34s serial flash/programming cable Richard Wahl 2 2,603 12-04-2013, 11:14 AM
Last Post: Barry Mead
  Solver issue with HP 17BII - different from 19BII Jeff Kearns 13 4,824 11-28-2013, 02:36 AM
Last Post: Don Shepherd
  HP Prime: run a program in another program Davi Ribeiro de Oliveira 6 2,783 11-11-2013, 08:28 PM
Last Post: Davi Ribeiro de Oliveira
  WP 34S/43 ?'s Richard Berler 3 2,128 11-10-2013, 02:27 AM
Last Post: Walter B
  My FrankenCulator (wp-34s) FORTIN Pascal 4 2,246 11-09-2013, 06:18 PM
Last Post: FORTIN Pascal
  WP 34S Owner's Handbook Walter B 5 2,752 11-09-2013, 05:34 PM
Last Post: Harald
  Another minor Prime hexagesimal issue Jonathan Cameron 1 1,417 11-08-2013, 02:37 PM
Last Post: Michael de Estrada
  wp 34s overlay and programming. FORTIN Pascal 6 2,985 11-08-2013, 01:28 PM
Last Post: Nick_S

Forum Jump: