De-allocating memory locations on HP-35s


I'm getting acquainted with my new 35s and finding the transition from my daily driver, a 20s, pleasant; and the return to RPN very refreshing! I won a 41CX in a college design contest in 1989 and became hooked on HP. I do miss that calculator...

While getting to know my new 35s, I allocated the full 801 variable locations with indirect (i). I thought this was fine until I discovered the hard way, (memory full), that the amount of memory left for programming was trivially small. A calculator reset solved the problem but subsequent reading, plus trial and error, has not turned up a way to de-allocate memory once its assigned to variables.

Any ideas from those who understand this better than me?

Thanks so much! Great fourm,



The memory is dynamic - the more "storage" - the less "program" memory; so you should allocate only the number of storage registers you really need. To release memory taken by no longer used registers store zeros in them; the last not-zeroed one draws the border.

It's all clearly explained in the manual.



It's clearly explained in the manual, yet I couldn't get it to release memory. I thought perhaps there was a non-zero value at 801 but it turned out that they were all set to zero.

I suspect it doesn't actually work as the manual says it should.


I don't have my manual handy, from memory it all worked; there are a few quirks with the calculator and the manual - all available through this forum - google it for HP-35S bugs


Or go to the HP35s bugs article.

- Pauli


Press RightShift-Clear, then pick CLVARx (item 6). You'll be asked for a number; this is the highest numbered variable that you want to keep. Every indirect register past that number will be wiped/deallocated.


Dave Britten,

Wow! It works!! and so easily. Thank you for pointing out the obvious that I had missed.


Or go to the HP35s bugs article.

- Pauli

Pauli - I want to add another small bugette to your post but I don't want to edit your post directly so if you agree with this one, could you add it please?

In most HPs, if you want to enter 10^6 for example, you just press E or EEX then 6. With the 35s, you have to enter 1 then E and 6 which adds an extra keystroke and shouldn't be necessary. It also adds inconsistency with nearly all HPs from the Voyagers onwards.

I tried this out on a few LCD HPs at random and the only one that needed the 1 was the 19B which otherwise took the E to be part of an alpha message so went into alpha edit mode.

Small but lots of small things add up!


Possibly Related Threads...
Thread Author Replies Views Last Post
  12C App kostenlos bei / Android Frank Boehm (Germany) 16 2,548 11-20-2012, 02:24 PM
Last Post: Luiz C. Vieira (Brazil)
  [hp-48] Jean Michel Ferrard "La Maitrise de la HP48 - Tome 2" programs? jerome ibanes 0 547 10-07-2012, 01:33 AM
Last Post: jerome ibanes
  PocketGuide in Portuguese / Guia de Bolso *inside* the HP 50g Software49g 4 1,247 07-18-2012, 02:03 PM
Last Post: Gerson W. Barbosa
  41 User Memory vs System Memory Gerry Schultz 6 1,445 07-01-2012, 12:02 AM
Last Post: Monte Dalrymple
  What's your de-facto calculator? Matt Agajanian 105 9,842 04-07-2012, 09:43 PM
Last Post: Eddie W. Shore
  HP-35S - Time Since Memory Reset Ilia 0 544 01-17-2012, 06:52 PM
Last Post: Ilia
  HP-35S hung in "Memory Clear" loop? Scott Newell 2 1,568 02-18-2011, 12:34 PM
Last Post: Scott Newell
  OT: Business Calculator from Marcus von Cube, Germany 4 1,049 01-18-2008, 03:28 AM
Last Post: Marcus von Cube, Germany
  HP 35s MEMORY FULL (well, not really!!) EL 3 802 01-14-2008, 05:02 PM
Last Post: EL
  clearing indirect memory in a program on 35s Don Shepherd 0 497 11-25-2007, 12:35 PM
Last Post: Don Shepherd

Forum Jump: