AVR_uart

Simple library based on cyclic buffer to handle sending bytes from uC to device using UART on AVR ATMega328p. Works on new chips like ATMega4809.

Tested on:

• ATMega328p
• ATMega4809

Notes

• TX_BUFF_SIZE should be power of two.
• Using ATMega328p with 16MHz crystal and setting U2X0 to 1, max baudrate can be as high as 2_000_000.
• Default settings is 8 bits per frame, no parity and 1 stop bit.

Functions

void uart_init();

Setup uart transmitter for given BAUD rate set in uart.h

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void uart_putc( char c );

Send only one character.

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void uart_puts( char * c );

Send C string, string have to be \0 terminated.

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void uart_puts_P( const char *s );

Send string as well, but from PROGMEM. For example: uart_puts_P( PSTR("Hello") );

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void uart_putd( uint8_t byte );

Send byte as decimal integer.

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void uart_puth( uint8_t byte );

Send byte in hex format.

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void uart_putb( uint8_t byte );

Send byte in binary form.

Note that putb and puth function does not send any prefix e.g 0b or 0x

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void uart_putbuf( uint8_t * buf, uint8_t len, char * label );

Send given buffer in hex format with label, for example: HappyLabel: A2B7CC20\r\n

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void register_uart_rx_event_callback(void (*callback)(void *buf));

Register callback function to call, when new line got received.

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void uart_get_str(char *buf);

Event function that run in main, non-blocking while loop. This function invoke callback.

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