Can't upload with to M5Atom on macOS Big Sur

  • I'm having trouble with uploading to an M5Atom using on macOS Big Sur 11.2.2 with the error:

    A fatal error occurred: Timed out waiting for packet header

    I've tried to use the Updater_FW20200422 (suggested in another thread), but get another error with that tool:

    Detecting M5Stack products.
    Find M5Stack products.
    Kernel driver deteched.
    Apply magic success.
    Fail to cast magic stage 2, please contact vendor.
    Waiting for device in DFU mode.....................%

    Otherwise the serial port works and I am able to use to read_mac:

    dean@lucky13 razzle % --port  /dev/cu.usbserial-7D52471593 read_mac v3.0
    Serial port /dev/cu.usbserial-7D52471593
    Detecting chip type... ESP32
    Chip is ESP32-PICO-D4 (revision 1)
    Features: WiFi, BT, Dual Core, 240MHz, Embedded Flash, VRef calibration in efuse, Coding Scheme None
    Crystal is 40MHz
    MAC: 50:02:91:92:3e:e8
    Uploading stub...
    Running stub...
    Stub running...
    MAC: 50:02:91:92:3e:e8
    Hard resetting via RTS pin...

    Any suggestions on how to proceed?

  • Also, I updated the CP210x Macintosh OS VCP Driver to v6 and that didn't help.

  • Hello Dean

    according to the description the M5Atom requires an FTDI driver.

    Note: I don't have a Big Sur installation, so I cannot tell if that will actually help.


  • Thanks for the suggestion, @felmue, but I figured out the problem!

    The default baud rate of 460800 is too fast for this device. If I specify --baud 115200 (in platformio.ini, that would be upload_speed = 115200) it works.

    Maybe this will be useful to someone else in the future.