UART communication between two RP pico

[IsaNocNoc]

Hello, I have been trying to communicate two Raspberry Pi Pico via UART communication and it didn't work, I have tried many things but it just doesn't work. This is the last code I am working on to send and receive a simple text and display it on an OLED screen.

Pico transmitter:

import machine
import utime

# Configurar el puerto UART
uart = machine.UART(1, baudrate=9600, tx=machine.Pin(8), rx=machine.Pin(9))

led=machine.Pin(20, machine.Pin.OUT)

# Función para enviar texto a través de UART
def enviar_texto(texto):
    uart.write(texto)

while True:
    texto_a_enviar = "Hola desde la Raspberry Pi Pico\r\n"
    enviar_texto(texto_a_enviar)
    led.value(1)
    utime.sleep(0.1)
    led.value(0)
    utime.sleep(1)  # Puedes ajustar el intervalo de envío según tus necesidades

Pico receiver:

from machine import Pin, I2C, UART
import utime
from ssd1306 import SSD1306_I2C

# Set up the OLED display
i2c = I2C(1, scl=Pin(7), sda=Pin(6))
oled = SSD1306_I2C(128, 64, i2c)

# Configurar la conexión UART (TX: Pin 0, RX: Pin 1)
uart = UART(1, baudrate=9600, tx=Pin(4), rx=Pin(5))

# Configurar el pin 16 como salida
led = Pin(14, Pin.OUT)

while True:
    try:
        datos_recibidos = uart.read(1)  # Leer un byte de datos
        if datos_recibidos:
            texto = datos_recibidos.decode('utf-8','replace')
            print(texto)

            # Borrar la pantalla OLED
            oled.fill(0)

            # Mostrar el texto en la pantalla OLED
            oled.text("Recibido:", 0, 0)
            oled.text(texto, 0, 16)

            # Actualizar la pantalla OLED
            oled.show()

            # Encender el LED al recibir datos
            led.value(1)

            # Esperar un momento antes de apagar el LED
            utime.sleep(0.1)
            led.value(0)
    except KeyboardInterrupt:
        break

# Cerrar la conexión UART al salir
uart.deinit()

[robert-hh]

A few coments:

• The Pin numbers for UART are GPIO numbers, not board pin numbers. So Pin(4) is board pin No. 6.
• Did you cross RX and TX, so RX board 1 to TX board 2 and TX board 1 to RX board 2?
• Did you connect GND between the two boards as well?
  In the sample script you receive and show the text character by character. Since the last character you send is NL, you end up with an empty screen.

[IsaNocNoc]

Thanks, I had not crossed the cables of the uart connections