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DM42 - Blinking display - Printable Version

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DM42 - Blinking display - pinkman - 12-10-2023 09:40 PM

Hi everyone,
I thought this subject was already addressed, but I can't find any thread about it.

My DM42 has a blinking or flashing display, quite regularly.
Video here :
https://drive.google.com/file/d/1c06ool08_XELw-TD15xPkuwsyJjHnv5a/view?usp=drive_link

I tried to reset the calc, to flash the firmware again, to reset RefLCD to 7 (111b), ... none of these worked.

Any idea?

Thanks,
Thibault


RE: DM42 - Blinking display - rprosperi - 12-11-2023 02:07 AM

Have you tried replacing the battery? Use a brand new, high-quality CR2032 such as Energizer.

I would not call this an obvious solution, but when batteries (especially cheap ones) are near the edge of sufficient charge, odd behaviors have been reported, so this super-easy procedure should be explored. Assuming so, please report good/bad results.


RE: DM42 - Blinking display - pinkman - 12-11-2023 08:38 PM

Definitely the battery!
Even when plugged on usb power.
Thanks a lot Bob.


RE: DM42 - Blinking display - brouhaha - 12-11-2023 09:03 PM

I don't know about the more recent DM32, but in general Swissmicros calculators don't use USB for power, only for data.


RE: DM42 - Blinking display - polbit - 12-11-2023 10:14 PM

(12-11-2023 09:03 PM)brouhaha Wrote:  I don't know about the more recent DM32, but in general Swissmicros calculators don't use USB for power, only for data.

They most certainly do, that’s how you get high speed. They are limited on battery power to low power mode.


RE: DM42 - Blinking display - rprosperi - 12-12-2023 01:52 AM

Well, you're both right.

The DM1x/DM41 do not take power from USB.

The DM42 and DM41X use USB power and when available, run at a higher clock speed.

The DM32 will run from USB power, but still runs at the same speed when USB power is available.


RE: DM42 - Blinking display - brouhaha - 12-12-2023 06:47 AM

(12-12-2023 01:52 AM)rprosperi Wrote:  Well, you're both right.

The DM1x/DM41 do not take power from USB.

The DM42 and DM41X use USB power and when available, run at a higher clock speed.

The DM32 will run from USB power, but still runs at the same speed when USB power is available.

I thought the DM42 and DM41X didn't either. I'm glad to be wrong about that. Thanks for the correction!