External power to header ?

  • Need to connect 5V power direct to header and remove battery. No clear what header pin to connect to - 5V ?, BAT ? or the mysterious HPWR pins ? Anybody tried this yet ? Thanks.

    1. The easiest is to use the USB cable and connect the 5V to it.
      2.If you do not need a battery, you can connect to pin 5 on the bus.
      3.I'm going to use such a power scheme. Red lines are new wires.
      HPWR is not used in M5Stack now. it is presented only on the bus.

  • @x-dron I guess you mean connect to the 5V not pin 5. Pin 5 is GND. What happens if power is supplied to 5V pin and then you connect USB at same time for programming - I suppose you could make a special USB programming cable with the USB 5V disconnected.

  • @drwino
    I'm sorry for missprint. Of course pin "5V". :)
    I said the best and most problemless way is to use the usb connector of M5Stack. You could make a special USB cable only with 5V.
    All other methods have nuances.
    See M5-Core-Schematic.
    The simplified power scheme looks like this.
    VCC_5V, VCC_3V3, Vbat are connected to the bus, V_USB is not.
    if you connect external power to VCC_5V then

    • A special USB programming cable with the USB 5V disconnected 'll not work. Course CP2104 is not powered.
    • If you want to program simply turn off the external power supply 5V. For example to use a jumper.
    • You can try to use a diode. But I do not have confidence.
    • The battery is not charged.
      I want to connect external 5V power to the V_USB wire and remove the USB-fuse.
      In this case all will powered and 5V from the USB is disconnected. Battery works too.
      All must have a common GND.

  • Thank you for the detailed reply. I will try some of the options but first I will order a few M5Stacks so life can continue if we get blue smoke !

  • @drwino
    Good luck.