Screen stopped working, nonsense AXP data

mdevel1

Hi,
I've got two pieces of M5StickC a few days ago. After trying out some of the example codes, the display stopped working in one of them (similar to the "M5StickC screen don't work" topic). I uploaded a small test program into it, which writes to serial port, to see if the other parts were still operating. Incidentally this program dumps data from the AXP chip and the results were surprising:

Output from the one without working display:

GetBatState: 1
GetCoulombchargeData: -1
GetCoulombdischargeData: -1
GetCoulombData: 0.0000

GetBatVoltage: 4.7685
GetBatCurrent: 0.0000
GetVinVoltage: 7.3695
GetVinCurrent: 2709.3750
GetVBusVoltage: 7.3695
GetVBusCurrent: 1625.6250

GetTempInAXP192: 288.8C

GetBatPower: 2362232.0000
GetBatChargeCurrent: 2167.5000
GetAPSVoltage: 6.0690
GetBatCoulombInput: 23860.5645
GetBatCoulombOut: 23860.5645

GetWarningLevel: 1

Output from the correctly working one:

GetBatState: 1
GetCoulombchargeData: -1
GetCoulombdischargeData: -1
GetCoulombData: 0.0000

GetBatVoltage: 3.5805
GetBatCurrent: -58.5000
GetVinVoltage: 2.6520
GetVinCurrent: 0.0000
GetVBusVoltage: 0.0000
GetVBusCurrent: 0.0000

GetTempInAXP192: 20.0C

GetBatPower: 266.9931
GetBatChargeCurrent: 0.0000
GetAPSVoltage: 3.5784
GetBatCoulombInput: 23860.5645
GetBatCoulombOut: 23860.5645

GetWarningLevel: 0

Both outputs were generated while the stick was running on its internal battery.
The source is on github: https://github.com/mdevel1/M5StickC_Battery_Monitor

After finding and removing two loose magnets inside the case (see "Loose magnets inside can short the battery and other components" topic), and power cycling the stick, the AXP chip somehow returned into a working state, the dumped values are back to normal (except which didn't make sense before), and the display is working too.

mdevel1

For the record: the coulomb counter data is fixed, but still undocumented in the newest version of the library (not released yet, only on Github).
There was another issue with the newest version, with a fix that is not yet merged, and available only as a pull request.