robertobenjami/stm32_uart

stm32 uart driver (multi uart, interrupt, adjustable circ buffer)

Stm32_uart driver

This driver also uses an interrupt and an adjustable buffer for sending and receiving. When receiving, it is possible to use a callback function for each character received. Thus, it is possible e.g. to detect the end of line character. Initialization will occur during the first use, so there is no uart_init function.

Can be used in microcontroller families

• stm32f0xx
• stm32f1xx
• stm32f2xx
• stm32f3xx
• stm32f4xx
• stm32f7xx
• stm32h7xx

Example app

• app_uart_test: This program shows how to receive and forward text data received on a serial line with line-by-line processing.

Uart functions

• uartx_sendchar(char c): send one character to usart note: if the TX buffer is full, it will wait until there is free space in it

• uartx_getchar(char * c); receiving a character on uart rx note: if return = 0 -> no characters received (not block the program from running) if return = 1 -> &c = received character

• uartx_cbrx(char rxch): if you want to know that a character has arrived, do a function with that name (optional) note: attention, it will be operated from an interruption!

• uartx_cbrxof: if you want to know that an RX buffer is overflowed, do a function with that name (optional) note: if this function is enabled, RX data loss has occurred attention, it will be operated from an interruption!

Uart settings in uart.h (see the comments in this header)

f0, f2, f3, f4, f7, h7 family:

• UARTx_RX, UARTx_TX: port name, pin number, AF number (if not used -> X, 0, 0)

f1 family:

• UARTx_RX, UARTx_TX: port name, pin number (if not used -> X, 0) note: see the data sheet which pin can be adjusted it is possible to use only the transmission or only the reception on its own
• UARTx_REMAP: The location of the uart pins can be changed (see in the datasheet)

all family:

• UARTx_BAUDRATE: Baud rate (bit/sec) note: if Baud Rate = 0 -> this uart not used

• TXBUFx_SIZE, RXBUFx_SIZE: buffer size (4,8,16,32,64,128,256,512,1024,2048,...) note: the buffer size should be (2 ^ n) !

• UARTx_PRINTF (printf redirect): 0 -> printf to uart disabled, 1 -> printf to uart eanbled note: can only be active on one usart

• UART_X_CLK: USART source frequency (see the comment in the header file)

• UART_PRIORITY: UART RX and TX interrupt priority (0..15) note: 0 = the highest priority, 15 = the lowest priority