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iam4722202468 / ThinkpadBattery

Open source Thinkpad T420 battery design
MIT License
258 stars 23 forks source link

Help me please. The voltage of 12367mV is displayed all the time, it always shows 100% of the charge #6

Open Naughtydog2004 opened 3 years ago

Naughtydog2004 commented 3 years ago

Hello. Can you please tell me which command controls the battery state of charge at 100% and charge / discharge mode? I can manage charge percentages with the byte reply0x0D command. But my laptop still shows 100% and won't charge the battery. By the way, the voltage from the resistor divider also does not change in any way and is transmitted to the SMBus as 12367mV (although, separately from this program, the code for measuring the voltage functions properly through the analog pin A3 on the arduino nano). Thanks in advance. https://drive.google.com/file/d/1x5DdUYXAxN2JYD1_1s9keKdGmnjLt5Kj/view?usp=sharing

iam4722202468 commented 3 years ago

Looking at my code, it looks like reply0x0F is what handles the % charged, try manually setting the charge value to something and checking if that changes the charge of your device. If it doesn't, then your device might need other packets than just the 0x0F one. Not all implementations of the smbus are identical for all devices

iam4722202468 commented 3 years ago

As for the voltage divider, there's a chance I screwed something up and it doesn't actually work, really hoping that isn't the case though... either way, i'll probably redo a few parts of this in around 4 months from now. The idea is to make a small pcb with a 3s bms and attiny combined, that can be programmed for any device.

Naughtydog2004 commented 3 years ago

Thank you! If I can fix this, then I will inform you

samipfjo commented 2 years ago

I think 0x0f() is incorrect, unless the Thinkpad battery departs from the SMBus spec (which is entirely possible). Command 0x0f is RemainingCapacity(), which is expressed as mAh or mWh depending on the value of 0x03 bit 15 (aka CAPACITY_MODE): 0 for mAh and 1 for capacity/10 mW/mWh. The calculation in 0x0f is identical to 0x09 (Voltage()) above it, perhaps it was a copying mishap?

iam4722202468 commented 2 years ago

@luketimothyjones yes this does look like an issue. When making this I didn't really know what I was doing, and it looks like I did just copy it. Feel free to pr a fix