NoVRAM bug reported (and corrected!!)



#2

Hi NoVRAM owners (current and future ones... ;-)

On Thursday, Miki Mihajlovic reported a nasty bug in the NoVRAM module power management.

After receiving his .HEX file and checking it in the Test-NoVRAM (Breadboard version of a standard one) it was determined that it was a Software issue.

Symptom: Your batteries go flat in a couple of weeks if you keep the NoVRAM module plugged in while in deep SLEEP (OFF) mode.

Culprit: FM24C256 RAM power line was not properly handled, so it remained alive regardless the 41 power was ON or OFF, draining over 0.5mA thru its data bus bias resistor.

Solution: (Obviously) Turn said RAM off at the end of "every" 41 power cycle.

A new NoVRAM-H.ASM file correcting this bug is available for download, I must keep the file name but you can tell one from another by looking at the time-stamp:

Old file is Jun 29 while the newer one is Aug 21, simply replace the old one with this:

http://www.iespana.es/clonix-41/NoVRAM-H.asm (Right click -> Save Target As... )

The NoVRAM-HEPAX.ZIP has also been updated.

My apologies for the inconveniences and thanks Miki for reporting this bug.

Diego.
123456


Possibly Related Threads...
Thread Author Replies Views Last Post
  Has anyone reported this bug to HP? Allen L. 4 444 01-10-2013, 07:41 PM
Last Post: Manolo Sobrino
  NOVRAM 64 / HEPAX bug? M. Joury 2 319 11-03-2012, 02:49 PM
Last Post: M. Joury
  Beta 41CL --> Best CL UTILs to burn in NoVRAM 64? Gene Wright 5 441 07-01-2012, 03:06 PM
Last Post: Matt Kernal
  NoVRAM 64 USB programmer Gene Wright 4 401 06-29-2012, 11:43 AM
Last Post: Diego Diaz.
  Non-HEPAX configurations for NoVRAM/NoV-32 Diego Diaz 1 220 02-07-2012, 07:27 AM
Last Post: Ignazio Cara (Italy)
  NoVRAM-M and NoV-32-M cgh 6 506 02-01-2012, 05:50 PM
Last Post: Richard Wagoner
  HP-41CL & NoVRAM/NoV-32 issue fixed... ;-) Diego Diaz 8 595 12-21-2011, 06:25 PM
Last Post: Diego Diaz
  WP 34S version 2.3 (corrected) Eddie W. Shore 33 1,733 12-12-2011, 03:52 PM
Last Post: Walter B
  Corrected command to build WP 34S assembler tables Neil Hamilton (Ottawa) 0 139 07-25-2011, 06:38 AM
Last Post: Neil Hamilton (Ottawa)
  NoVRAM / HEPAX MCODE Question Jeff Davis 2 265 12-06-2010, 05:01 AM
Last Post: Frido Bohn

Forum Jump: