Cant get 5v output to work from a stripped down M5Core2. Urgent Help Needed



  • So i will set the stage. I found the M5core2 as the almost perfect solution for my project. I stripped out the Core2 pcb from the case and removed the LCD/Touchscreen as these were not needed, I also disconnected the battery and confirmed 5V output on portA and connected my project up. After a short while I noticed the 5v had disappeared (i'm not constantly monitoring). Also any calls to read the APX192 input voltages just returned zero. What could be wrong? The core2 was well insulated, so nothing shorted. The voltages still read zero after i reconnect the battery. The battery does appear to take a charge and the power button functions normally but i cant read the voltage and i cant get 5V output. I checked and the boost converter is not blown, the AXP192 has the enable line for the boost converter set low, and when i force it to 3.3v manually with a jumper 5v comes out of the port again.
    I'm kind of at a loss and I really need to resolve this quick.
    Is it possible that this was caused by running the board with the screen and or touch disconnected? Maybe the M5unified library dose not know what board is connected since the hardware no longer matches and therefore the AXP192 never gets initialized?

    Thanks in advance for any suggestions.



  • @NotInTheMafia The touchscreen uses i2C, so does the AXP192. What could be happening is an i2C bus error, due to the address of the touchscreen not being present, and no more data being sent to the AXP192, resulting in no power past that point.