Custom Kernel for MT6739 Smartwatches

Android Software & Development
122

It seems possible to limit the charger voltage, i’m currently testing how reasonable it is to reduce the voltage to 4.2V (instead of 4.35V).

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123

One thing for sure, the battery will stop charging at that voltage when reached.
I believe many people who doesn’t understand will asked why battery can’t be charged to 100% so it will be wise to add that note too (old fashioned readme should be enough)

124

Added the 4.2V charger cut-off voltage.

Edit:
This change has been added to the original post.

Source can be found here:

1 Like
125

My understanding is that when the initial capacity is manually kept at a lower level, it should reduce the battery deterioration in the long run which results in a (in comparison) higher capacity after 200+ charge cycles.
The Optimus Pro stops charging at around ~93%.

126

yes that’s correct.

as for optimal charge I recommend is until 80%, or perhaps around 4.05V.

127

That’s probably set too low for a reasonable usage, a tradeoff is maybe 4.15V somewhat around ~90%.

128

fair enough :+1:

129

I just saw this. I am using your 900 mhz prebuilt, it really makes my allcall awatch gt run cooler. I love it. I am going to try this as well. Let’s see at what percentage it will cut charging.

130

I tried it in Allcall Awatch GT. It stopped charging at 90 %. Thank you very much!

131

@none sir, have you tried even lower workable cpu frequencies?

132

Good question. Like 700 mhz.

133

“The file you are trying to download is no longer available.”

134

It’s available here, but it’s currently untested so it might not even boot.

135

ah yes, in case anyone have problems after flashing older version kernel for testing, like nvram error like @tweakradje or in my case my watch can’t enter deep sleep after receiving SMS (weird indeed, but after flashing only both system and boot the problem persist. and that’s after using 3 different firmware) or any unwanted bugs, perhaps it’s better to flashing full fimware then flash new kernel release.

But this better done if you encounter problems, if not stick to what you are doing lol :laughing:

136

sorry to bother but I have a problem with the installation. Apparently everything was completed according to the instructions, but to no avail. Can you tell me how to upload it correctly?

137

@Patryk_Roszkowski
Check here for a quick tutorial.

@Giorgos_Tsarouchas
Yes, but i think the current 900MHz are already the sweetspot between performance, efficiency and power saving.
Reducing the frequency further will decrease performance without much gain in either energy saving or heat output.

Edit:
Updated all kernel images on the original post and added a short instruction for the flashing process.

4 Likes
138

I am using underclocked to 910 MHZ + charging up to 90 % Kospet Prime boot.img + Scatter file for a while. I enjoy using it. Recently I found that my front camera is showing reddish or blueish depending on the light. I switched back to regular boot.img + Scatter file, it was back to normal again. Is there a setting for this in Android?

139

Please try if this is fixed on the new prebuilt: Prime.zip

1 Like
140

Thank you for the quick reply. I downloaded it to the watch. Front Camera is still reddish. That is fine. I will live with it:-)

2 Likes
141

You’re right, something is definitely off:

I will try to find a fix for that.

Edit:
It actually looks like a bug on the original firmware, the stock boot.img has three camera sensor drivers included:

gc5025_mipi_raw gc0339_mipi_raw gc5035_mipi_raw

And for some reason it uses the GC5035 id for the GC0339 sensor:

LensMCU : LensMCU[CurrSensorDev]0x0002 [CurrSensorId]0x5035

The custom kernel defaults to the correct id (0xC8 = GC0339):

LensMCU : LensMCU[CurrSensorDev]0x0002 [CurrSensorId]0x00c8

So the GC0339 somehow has to use the GC5035 configuration (at least on the Android side) to work correctly.

4 Likes