UART

Example

Continuously exchange data between uart1 and uart2 to achieve bidirectional communication.

from m5stack import *
from m5ui import *
from uiflow import *

setScreenColor(0x292929)

label0 = M5TextBox(15, 106, "Slave Baud", lcd.FONT_Default, 0xFFFFFF, rotate=0)
label1 = M5TextBox(12, 130, "115200", lcd.FONT_DejaVu40, 0x02c7fc, rotate=0)
label2 = M5TextBox(15, 20, "TX", lcd.FONT_Default, 0xFFFFFF, rotate=0)
label3 = M5TextBox(139, 20, "RX", lcd.FONT_Default, 0xFFFFFF, rotate=0)
label4 = M5TextBox(12, 40, "G17", lcd.FONT_DejaVu40, 0x00ff38, rotate=0)
label5 = M5TextBox(136, 40, "G16", lcd.FONT_DejaVu40, 0x00ff38, rotate=0)
label9 = M5TextBox(173, 106, "/", lcd.FONT_DejaVu72, 0xFFFFFF, rotate=0)
label10 = M5TextBox(199, 125, "PC default baud", lcd.FONT_Default, 0xFFFFFF, rotate=0)
label11 = M5TextBox(224, 149, "115200", lcd.FONT_Default, 0xFFFFFF, rotate=0)

uart1 = machine.UART(1, tx=1, rx=3)
uart1.init(115200, bits=8, parity=None, stop=1)
uart2 = machine.UART(2, tx=17, rx=16)
uart2.init(115200, bits=8, parity=None, stop=1)
while True:
  if uart1.any():
    uart2.write(bytes(uart1.read()))
  if uart2.any():
    uart1.write(bytes(uart2.read()))
  wait_ms(2)

API

uart1 = machine.UART(1, tx=14, rx=13)
uart1.init(9600, bits=8, parity=None, stop=1)

• Sets the TX and RX pins and configures the communication parameters (baud rate, data bits, parity, and stop bits) for serial communication.

uart1.write('' + "\r\n")

• Sends a string via uart1, followed by a carriage return and newline to signify the end of the line.

uart1.write('')

• Sends a string via uart1.

uart1.write(bytes([0, 0, 0]))

• Sends an array containing three byte values via UART1.

str(uart1.read())

• Reads the data received by UART1 and converts it to a string.

label0.set_text(str(uart1.read(10)))

• Reads up to 10 bytes of data received by UART1, converts it to a string, and sets it as the text of label0.
  • "10": Sets the maximum number of bytes.

str(uart1.readline())

• Reads a line of data received by UART1 and converts it to a string.

str(uart1.any())

• Checks if there is data available to read in the UART1 receive buffer and converts the result to a string.