DB48X: HP48-like RPL implementation for DM42

[spiff72]

I have an possibly odd question.

My DM42 (running DB48x) is showing the low battery warning today for the first time. I figured that this is probably legit because the voltage indicator in the menu bar has been gradually decreasing, and it dropped below 2.6v now.

I am at work but I have a stash of crummy CR2032 batteries here that I thought I could at least install and use until I get home and put a better quality battery in tonight.

However, when I swapped in one of these suspect batteries, I still get the error message and can't use the calc unless it's plugged into USB power.

I did check the battery voltage with a multimeter and it was about 3.1V before I installed it. I just pulled the back off the calc and carefully checked the voltage while it is installed and in the "on" state (currently displaying the low voltage warning). I measure 3.15v despite the voltage level being reported by the calc in the sub-2.6v range.

Could something have changed in the latest FW version that might cause this? It seems like it's not reading the voltage correctly, but I never tried measuring the voltage in-circuit with previous FW versions.

Thanks!