@felmue I get output on pin 18 only (Port.C RX pin), pin 17 is always at 3.2V.

When I tap directly into the pin header on CoreS3 the PC_TX is at 3.2V.

It must be a faulty CoreS3 then.

Thanks for your help.

@felmue I tried different pins order, CoreS3 and Core2. Core2 works fine (UART on Port.C works) but CoreS3 gives no output on Port.C. I confirm each test result with a scope.

The hardfware is stacked like this:
[Core2/CoreS3]
[stepmotor drivert v1.1]
[din base]

Hi There,
I am having issue with CoreS3: UART on Port.C does not work in Platformio with Arduino framework.

The same code works with Core2 v1

Already tried swapping pin 17 and 18 but nothing on the oscilloscope.

Already tried using serial2 instead of HardwareSerial 2.

Did anyone face similar issue?

main.cpp:

#include <Arduino.h>
#include <Wire.h>

#include <M5Unified.h>

#define CORE_S3

#ifdef CORE_S3

    static const int SERVO_UART_TX = 17;
    static const int SERVO_UART_RX = 18;

#elif defined CORE_2

    static const int SERVO_UART_TX = 13;
    static const int SERVO_UART_RX = 14; 
#endif


//HardwareSerial SerialServo(2);

void setup() {
    M5.begin();  // Init M5Core.  初始化 M5Core
    // Serial2.begin(unsigned long baud, uint32_t config, int8_t rxPin, int8_t
    // txPin, bool invert)
    Serial.begin(115200);
    // Serial2.begin(115200, SERIAL_8N1, 13,
    //               14);  // Init serial port 2.  初始化串口2
    Serial2.begin(1000000, SERIAL_8N1, SERVO_UART_TX, SERVO_UART_RX);  // Init serial port 2.  初始化串口2

  M5.Lcd.printf("Started");
  delay(200);
}

void loop() {
    Serial.write("aaaaaaaaaaaaaaa");
    Serial2.write("bbbbbbbbbbbbbb");
    delay(100);
}

platformio.ini

[env:m5stack-cores3]
monitor_speed = 115200
monitor_dtr = 0
monitor_rts = 0
platform = espressif32
board = m5stack-cores3
framework = arduino
lib_deps = 
  m5stack/M5Unified@0.2.3