Tech Support: ESP32 + Ethernet Carrier = no boot. invalid header 0xffffffff

Development Boards MicroMod
1
  • - Micromod single slot main board
  • - Micromod ESP32 Processor
  • - Micromod Ethernet

    • If i have only the ESP32 hooked up to the main board I am able to to upload a simple sketch (LED blink) and communicate with the processor via serial. (notwithstanding the hideous bug here: viewtopic.php?f=182&t=55461&p=239992#p239992)

    However if I add then power down, and insert the Ethernet function board and power back up (via a PC’s USB) the sketch no longer runs (LED not blinking), and on a serial monitor I see this:

    rst:0x10 (RTCWDT_RTC_RESET),boot:0x33 (SPI_FAST_FLASH_BOOT)
invalid header: 0xffffffff
invalid header: 0xffffffff
invalid header: 0xffffffff
invalid header: 0xffffffff
invalid header: 0xffffffff
invalid header: 0xffffffff
invalid header: 0xffffffff
ets Jul 29 2019 12:21:46

    This sequence repeats

    If I remove the Ethernet board the ESP32 seems to work fine again.

    Without the Ethernet board the main board’s lights are all lit except for “CHG”. When the Ethernet board is connected The lights on the main board are the same. The PWR light on the Ethernet board is also lit.

    In none of the above is any Ethernet cable attached.

    If I do use connect the Ethernet board to a PoE source, the PoE light is lit. The main board’s 3V3 and QWC are lit. VIN is not lit. The sketch does not run. If I then plug in a USB cable: VIN lights, and on the serial monitor I see the same message sequence

    Since this is the most basic test I can think of I’m at a loss as to what to do next.

    Thank you.

    2

    First, ensure the standard esp32 library is installed https://learn.sparkfun.com/tutorials/mi … rogramming

    Then, ensure you have altered the arduino sketch being loaded to match the esp32 micromod pin#s https://learn.sparkfun.com/tutorials/mi … no-example

    And try powering over PoE again - any change (does VIN on main board light up)?

    3

    Hi Russel,

    The board is selected in the board manager correctly, see attached images. I have used other ESP32 boards in this way without trouble. The basic sketches (LED blink, or plain serial.println every 500 ms) upload and run fine as long as the Ethernet board is not attached. I confirm with PoE powering the board only the Vin light is NOT lit.

    arduino_board-libs.png
    arduino_board-libs.png788×466 17 KB

    micromod-settings.png
    micromod-settings.png927×746 28.1 KB

    The sketch I am using does not use the Ethernet board’s functionality in any way, nor does it include any Ethernet libraries so I can’t see how the pins are yet relevant. The only pin I’ve used is the LED pin. I also tried the same sketch without using the LED pin (serial writing only), same result.

    Sketch:

    int ledPin = 2;

void setup() {
  // put your setup code here, to run once:
    pinMode(ledPin, OUTPUT);
    Serial.begin(115200);
}

void loop() {
  // put your main code here, to run repeatedly:
    Serial.println("Running...");
    digitalWrite(ledPin, HIGH);
    delay(500);
    digitalWrite(ledPin, LOW);
    delay(500);
}
    4

    Alright I guess I’ll have to return the parts. Too bad, I was hoping to use this system in a couple of my company’s instruments.

    5

    Drats - file for a return or refund (preference) here www.sparkfun.com/returns (or contact vendor if purchased elsewhere) and we’ll get ya squared away