Backup battery problems

M7PKY
Posts: 25
Joined: Mon Feb 21, 2022 2:07 pm

Re: ALPHA version - Known problems

Post by M7PKY » Sun Oct 30, 2022 11:59 pm

VK3KYY wrote:
Sun Oct 30, 2022 11:55 pm
M7PKY wrote:
Sun Oct 30, 2022 11:07 pm
Thanks for the pointers. I loaded the stock firmware back on. It was one very messed up, unhappy radio until I reuploaded the codeplug, but I can confirm that this is indeed NOT the case. The clock correctly retains the time on battery pull.
Do you mean the hardware RTC is not running when the radio is not turned on, or not running when you pull out the battery ?

If its the latter then, this suggests the RTC battery has a connection to the battery directly, rather than the regulated 3.3V rail; which is only powered then the radio is turned on, because the regulators take currently which would flatten the battery if they were constantly on.
I mean the thing I read about is untrue. Pulling the battery has no effect. The RTC works correctly in all cases, suggesting the standard wiring you linked to is likely correct.

VK3KYY
Posts: 7478
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia

Re: Backup battery problems

Post by VK3KYY » Mon Oct 31, 2022 8:32 am

Euli1988 wrote:
Mon Oct 31, 2022 7:23 am
It also doesn't matter if the device is on, off, or charging.I've played through all scenarios.After about 10 seconds, all settings are gone.
Sounds like the battery is defective, as it is not holding charge

EA5JAQ
Posts: 86
Joined: Thu Jul 16, 2020 6:08 am

Re: Backup battery problems

Post by EA5JAQ » Mon Oct 31, 2022 2:16 pm

Hi,

I'm having a similar problem. If I don't turn on the radio in a couple days, all my settings are gone. Isn't there any way to store the settings in a non-volatile memory that doesn't rely in a battery, like with the GD-77, etc.? When I don't use my DM-1801 in months, all the settings are still there.

The rest of the firmware features work like a charm. Thanks for everything.

VK3KYY
Posts: 7478
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia

Re: Backup battery problems

Post by VK3KYY » Mon Oct 31, 2022 9:37 pm

EA5JAQ wrote:
Mon Oct 31, 2022 2:16 pm
Hi,

I'm having a similar problem. If I don't turn on the radio in a couple days, all my settings are gone. Isn't there any way to store the settings in a non-volatile memory that doesn't rely in a battery, like with the GD-77, etc.? When I don't use my DM-1801 in months, all the settings are still there.

The rest of the firmware features work like a charm. Thanks for everything.
How old is your radio?
Was it unused for a long time?
Did you check whether the same problem happens on the official firmware?

If the battery is defective, it should be replaced.

EA5JAQ
Posts: 86
Joined: Thu Jul 16, 2020 6:08 am

Re: Backup battery problems

Post by EA5JAQ » Tue Nov 01, 2022 7:27 am

It’s like a month old. I’ve been really busy with work so I didn’t use it that much (only to try the firmware). I’m gonna leave it on for the day today to see if it charges and if that solves the problem. But I remember that a couple weeks ago, I forgot to turn it off and it was on for like 12-ish hours, it should be charged. So either the battery is really bad and can’t hold the settings for more than a couple weeks, or mine is defective.

VK3KYY
Posts: 7478
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia

Re: Backup battery problems

Post by VK3KYY » Tue Nov 01, 2022 8:34 am

EA5JAQ wrote:
Tue Nov 01, 2022 7:27 am
It’s like a month old. I’ve been really busy with work so I didn’t use it that much (only to try the firmware). I’m gonna leave it on for the day today to see if it charges and if that solves the problem. But I remember that a couple weeks ago, I forgot to turn it off and it was on for like 12-ish hours, it should be charged. So either the battery is really bad and can’t hold the settings for more than a couple weeks, or mine is defective.
Leave the radio turned on for 24 or 48 hours when in the charger, and see if the battery has recovered its capacity

G4EML
Posts: 919
Joined: Sat Nov 16, 2019 10:01 am

Re: Backup battery problems

Post by G4EML » Tue Nov 01, 2022 10:11 am

I have done a few rough calculations.

The battery capacity is 1mAh.
The datasheet say that the current drain on vbat is around 1uA.
So, with a fully charged battery you would expect it to last for around 1000 hours.
That is about 6 weeks.

A new radio will probably have been sitting without a main battery for longer than that, so it might be expected the RTC battery starts off life fairly flat.

I don't know exactly what the charging current is but the data sheet for the battery suggests 0.01mA. So the charging time for a flat battery would be 100 hours.

Based on that the battery should last for roughly 10 times longer than it has been used.

So leaving the radio turned on in the charger for 24 hours may well be a good thing occasionally.

The official firmware stores most of its settings back to the codeplug and only really uses the battery for the RTC. So it might not be quite as noticeable if the battery goes flat.

Colin.

VK3KYY
Posts: 7478
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia

Re: Backup battery problems

Post by VK3KYY » Tue Nov 01, 2022 10:26 am

We could probably use the Flash memory for storage if people find that in normal use the backup battery keeps going flat.

The UV380 /RT3S doesnt have EEPROM that the GD77 uses for setting storage, which is better suited to storing things than Flash, but Flash would work.

The problem with using Flash is the eventual wear of part of the memory, but it would not be as bad on the UV380/RT3S as is on the RD5R which also only has flash but also does not have power management.

Whats strange is that ist highly likely that even new radios would have been sitting in storage for far longer than 6 weeks, and yet hardly anyone reports any problems with the settings not being retained.

Assuming the official firmware has the RTC enabled when it leaves the factory, then the batteries would be completely flat when most people receive their radio.

It seems unlikely that the official firmware had not been run on the radio prior to it being shipped, so unless there is some option to enable / disable the RTC in the official firmware, then the RTC would be running all the time the radio was in storage and transit.

I'm not at all familiar with the official firmware, so perhaps the RTC is disable by default, and only enabled when someone sets the time.


Anyway, this could be changed, but there are benefits to using the battery backed RAM and disadvantages to using the Flash, so we'd need to be sure it was necessary to change both the MD9600 and UV380 to use Flash for storage

G4EML
Posts: 919
Joined: Sat Nov 16, 2019 10:01 am

Re: Backup battery problems

Post by G4EML » Tue Nov 01, 2022 2:55 pm

The settings in the factory firmware are mostly (if not all) stored in the codeplug so that they can be changed in the CPS or in the radio. Hence they will be stored in flash. Probably the only thing people would notice if the battery was flat would be the clock setting and that would not be that obvious.

Provided people use the radio regularly then our method of using the battery backed ram works OK. In practice even if the settings are occasionally lost it doesn't take long to reset them.

Colin.

VK3KYY
Posts: 7478
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia

Re: Backup battery problems

Post by VK3KYY » Tue Nov 01, 2022 8:17 pm

G4EML wrote:
Tue Nov 01, 2022 2:55 pm
The settings in the factory firmware are mostly (if not all) stored in the codeplug so that they can be changed in the CPS or in the radio. Hence they will be stored in flash. Probably the only thing people would notice if the battery was flat would be the clock setting and that would not be that obvious.

Provided people use the radio regularly then our method of using the battery backed ram works OK. In practice even if the settings are occasionally lost it doesn't take long to reset them.

Colin.
Thinking about the RD5R, I remembered it does have EEPROM, but it dioesnt have the power management circuit, so on that radio we have to save to EEPROM every time there is a settings change or channel change etc

The UV380 has the power management circuit, but no EEPROM.

I think the official firmware does use the battery RAM, because I recall reinstalling the official firmware, doing some tests, and then reinstalling OpenGD77, and the radio displayed the settings update message, which means the settings Magnic number must have been changed

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