NoVRAM bug reported (and corrected!!)


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: (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.


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