TX of RP2040 mikroBUS™ Development Board is always high (3.3v)?

Community Development Platforms
1

Hi everyone,

I am currently testing with the board RP2040 mikroBUS™ Development Board. (https://learn.sparkfun.com/tutorials/rp … -guide/all)

I followed the hook up guide and am able to compile with Arduino.

I use the board setting by github user earlephilhower and set the board to “SparkFun Thing Plus RP2040”.

My goal is to use click board so I have to get the UART0 work (I guess it is UART0?).

However, no matter how I call Serial1.write(what_ever_some_val), the TX pin is always 3.3V measured by oscilloscope.

I am doubt if I have any setting wrong?

Here is my code for testing:

#define ENOCEAN_SERIAL Serial1
#define TX_PIN 0
#define RX_PIN 1

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);

  while (!Serial) {
  }

  Serial.println("Serial init - done");
  
  ENOCEAN_SERIAL.setTX(TX_PIN);
  ENOCEAN_SERIAL.setRX(RX_PIN);
  ENOCEAN_SERIAL.begin(57600);

  led_init();
  
  Serial.println("setup done");
}

void loop() {
  // put your main code here, to run repeatedly:
  Serial.println("loop - 3");
  
  led_on();
  delay(500);
  led_off();
  delay(500);
  
  ENOCEAN_SERIAL.println(1);
}

////////// LED //////////

void led_init()
{
  pinMode(25, OUTPUT);
}

void led_on()
{
  digitalWrite(25, 0);
}

void led_off()
{
  digitalWrite(25, 1);
}

Thank you in advance,

Lee

2

Is it always 3.3V no matter whatever code you upload?

3

Hi tepalia02,

Thank you for your reply.

Yes, it was always 3.3V.

And I have solved it by clearing the board (copying the flash_nuke.uf2).

Regards,

Lee