2.13 UART Module API Manual#
1. Overview#
The K230 integrates five UART (Universal Asynchronous Receiver/Transmitter) hardware modules internally. Among them, UART0 is occupied by the small core SH, UART3 is occupied by the large core SH, and the remaining UART1, UART2, and UART4 are available for user use. The I/O configuration of the UART can be referenced from the IOMUX module.
2. API Introduction#
The UART class is located in the machine module.
2.1 Example Code#
from machine import UART
# Configure UART1: Baud rate 115200, 8 data bits, no parity, 1 stop bit
u1 = UART(UART.UART1, baudrate=115200, bits=UART.EIGHTBITS, parity=UART.PARITY_NONE, stop=UART.STOPBITS_ONE)
# Write data to UART
u1.write("UART1 test")
# Read data from UART
r = u1.read()
# Read a line of data
r = u1.readline()
# Read data into a byte buffer
b = bytearray(8)
r = u1.readinto(b)
# Release UART resources
u1.deinit()
2.2 Constructor#
uart = UART(id, baudrate=115200, bits=UART.EIGHTBITS, parity=UART.PARITY_NONE, stop=UART.STOPBITS_ONE, timeout = 0)
Parameters
id: UART module number, valid values areUART1,UART2,UART4.baudrate: UART baud rate, optional, default value is 115200.bits: Number of data bits per character, valid values areFIVEBITS,SIXBITS,SEVENBITS,EIGHTBITS, optional, default value isEIGHTBITS.parity: Parity check, valid values arePARITY_NONE,PARITY_ODD,PARITY_EVEN, optional, default value isPARITY_NONE.stop: Number of stop bits, valid values areSTOPBITS_ONE,STOPBITS_TWO, optional, default value isSTOPBITS_ONE.timeout: Read data timeout time in ms.
2.3 init Method#
UART.init(baudrate=115200, bits=UART.EIGHTBITS, parity=UART.PARITY_NONE, stop=UART.STOPBITS_ONE)
Configure UART parameters.
Parameters
Refer to the constructor.
Return Value
None
2.4 read Method#
UART.read([nbytes])
Read characters. If nbytes is specified, read up to that number of bytes; otherwise, read as much data as possible.
Parameters
nbytes: Maximum number of bytes to read, optional.
Return Value
Returns a byte object containing the read bytes.
2.5 readline Method#
UART.readline()
Read a line of data, ending with a newline character.
Parameters
None
Return Value
Returns a byte object containing the read bytes.
2.6 readinto Method#
UART.readinto(buf[, nbytes])
Read bytes into buf. If nbytes is specified, read up to that number of bytes; otherwise, read up to len(buf) bytes.
Parameters
buf: A buffer object.nbytes: Maximum number of bytes to read, optional.
Return Value
Returns the number of bytes read and stored in buf.
2.7 write Method#
UART.write(buf)
Write a byte buffer to the UART.
Parameters
buf: A buffer object.
Return Value
Returns the number of bytes written.
2.8 deinit Method#
UART.deinit()
Release UART resources.
Parameters
None
Return Value
None