Scrambled data from ESP32-CAM-MB

[pauljurczak]

I'm using ESP32-CAM, which works fine with an external CP2102 USB/serial adapter, but gives me problems with two different ESP32-CAM-MB boards using these USB/serial chips:

- QinHeng Electronics HL-340
- CH340C

I'm testing with a simple blink script:

Code: Select all

#include <Arduino.h>

void setup() {
  Serial.begin(9600);
  pinMode(33, OUTPUT);
}

void loop() {
  digitalWrite(33, LOW);   
  delay(300);              
  digitalWrite(33, HIGH);    
  delay(300);              
  Serial.println("blink");
  Serial.flush();
}

It runs as expected with CP2102, but with 340 chips the data coming back from ESP32-CAM is scrambled or listening on USB port with serial monitor on PlatformIO, halts the blinking. Any idea how to fix it? I tried different baud rates with the same result.

[gribouille]

Have a look :
https://community.platformio.org/t/noob ... de/19117/5

You have to add this two lines to platformio.ini :
monitor_rts = 0
monitor_dtr = 0

You can also go to :
https://docs.platformio.org/en/latest/p ... onitor-rts

[pauljurczak]

Thank you, this solved my problem. For future readers, my issue was compounded with having two different types of ESP32-CAM boards. They have identical layout and differ only by ESP32-S module, which I just discovered. The modules with Espressif logo work just fine. They don't even need GPIO1 shorted to the ground when programmed with ESP32-CAM-MB. The other modules have AI-Thinker logo and I can't program them with ESP32-CAM-MB. I have to use an external USB/serial adapter and short GPIO1 to GND for programming.