[34S] occasional RTC reset upon power on

[John Galt]

Thank you Marcus. The symptoms are exactly as you described. I suspected it was due to marginal batteries, and that it might be related to this question.

It's also interesting to note that different battery manufacturers have different characteristics. The ones I'm using in this thread are from Maxell. The ones in the other are Panasonic. Whereas the Maxell voltage decreases gradually with use, the Panasonic voltage drops precipitously under load, only to recover significantly after the calculator shuts down.

Right now BATT shows the Maxell batteries at 2.8 V. That's low. The Panasonic might indicate 2.9 V, but under load that decreases suddenly, and in a manner that's obvious to the user (the calculator shuts down). I haven't been able to make the Maxell batteries crash under load while the calculator is in use. They appear to do so in a much less obvious way - the RTC reset. Or, a noticeable delay during power on.

The WP 34S is obviously very fast, even in SLOW mode. I wish there were a way to slow it down even more, to get more life out of the batteries or to provide more warning to the user that they're about to die. Perhaps CR2032 cells just weren't designed for the load it demands.

I just wish there were a better way of utilizing the low battery indicator... which is the subject of that other thread.