How to pc 910 cmos reset

I am using pc 910 and need to reset coms.
CMOS does not reset even after 24 hours after removing the built-in battery.
Please tell me how to reset cmos.

and welcome to our Community!

Depending on the system and the use-case (used as GPOS system = Windows, Linux or as AR embedded system = PLC), the’re possibly different battery-buffered memories inside the system (BIOS / RTC battery, SRAM battery, …)

Because you’re mentioned CMOS, I assume you’re talking about the BIOS / RTC reset, and you removed the battery which is accessible on the front of the APC.
If I’m wrong and you’re talking about SRAM memory (for example the so-called remanent variables, if the system is used as PLC), then, depending on the systems hardware configuration, maybe you have to open the APC and check / remove batteries installed on the PCI cards also.

And yes I agree, after 24 hours without power supply and no battery, the buffered BIOS values should be resetted.
But it’s also possible that some values aren’t stored in the battery buffered memory area, but in a non-volatile area that doesn’t need a battery at all.

So, what values do you expect to be deleted?
To reset the system to default values, you can enter the BIOS setup utility (display and keyboard is needed), navigate to the “Save & Exit” section, and use “Restore Defaults”, more information see here in the help.

Best regards!

1 Like

hi. Thank you so much for your reply
What I want is to reset the BIOS settings.
The current situation is that the USB is turned off in the bios settings, so the keyboard and mouse are not recognized.
I wanted to initialize the bios settings in cmos to recognize the keyboard and mouse, so I removed the battery, but it is not initializing.
Even if I remove the battery and reboot after 24 hours, the date and time are not reset and the data is not initialized.
I wonder if there is a cmos reset jumper setting like a regular computer.
Please tell me how to reset cmos bios settings
Thank you so much

Hi, as far as I know BIOS is reset to default after BIOS update. So if you remove CFAST card with OS, download BIOS update from webpage, modify start up file in way that pause and confirmation with any button is deleted, you generate another CFAST card with this modifed BIOS update, plug it into APC and restart it, it should theoretically starts automatically BIOS Update… try it :slight_smile:


The APC910 Manual states the following:

" When changing the battery in a voltage-free state, any BIOS settings made are retained (stored in voltage-safe EEPROM). The date and time must be set again since this data is lost during the change. "

Unfortunately, two ways to recover would be running a BIOS update from the CFast card as mentioned by Jaroslav or send it in for repairs.