diff options
Diffstat (limited to 'drivers/avr/uart.c')
| -rw-r--r-- | drivers/avr/uart.c | 170 | 
1 files changed, 0 insertions, 170 deletions
| diff --git a/drivers/avr/uart.c b/drivers/avr/uart.c deleted file mode 100644 index c6abcb6fe0..0000000000 --- a/drivers/avr/uart.c +++ /dev/null @@ -1,170 +0,0 @@ -/* UART Example for Teensy USB Development Board - * http://www.pjrc.com/teensy/ - * Copyright (c) 2009 PJRC.COM, LLC - * - * Permission is hereby granted, free of charge, to any person obtaining a copy - * of this software and associated documentation files (the "Software"), to deal - * in the Software without restriction, including without limitation the rights - * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell - * copies of the Software, and to permit persons to whom the Software is - * furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice shall be included in - * all copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE - * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, - * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN - * THE SOFTWARE. - */ - -// Version 1.0: Initial Release -// Version 1.1: Add support for Teensy 2.0, minor optimizations - -#include <avr/io.h> -#include <avr/interrupt.h> - -#include "uart.h" - -#if defined(__AVR_AT90USB162__) || defined(__AVR_ATmega16U2__) || defined(__AVR_ATmega32U2__) || defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__) || defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__) || defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__) -#    define UDRn UDR1 -#    define UBRRnL UBRR1L -#    define UCSRnA UCSR1A -#    define UCSRnB UCSR1B -#    define UCSRnC UCSR1C -#    define U2Xn U2X1 -#    define RXENn RXEN1 -#    define TXENn TXEN1 -#    define RXCIEn RXCIE1 -#    define UCSZn1 UCSZ11 -#    define UCSZn0 UCSZ10 -#    define UDRIEn UDRIE1 -#    define USARTn_UDRE_vect USART1_UDRE_vect -#    define USARTn_RX_vect USART1_RX_vect -#elif defined(__AVR_ATmega32A__) -#    define UDRn UDR -#    define UBRRnL UBRRL -#    define UCSRnA UCSRA -#    define UCSRnB UCSRB -#    define UCSRnC UCSRC -#    define U2Xn U2X -#    define RXENn RXEN -#    define TXENn TXEN -#    define RXCIEn RXCIE -#    define UCSZn1 UCSZ1 -#    define UCSZn0 UCSZ0 -#    define UDRIEn UDRIE -#    define USARTn_UDRE_vect USART_UDRE_vect -#    define USARTn_RX_vect USART_RX_vect -#elif defined(__AVR_ATmega328__) || defined(__AVR_ATmega328P__) -#    define UDRn UDR0 -#    define UBRRnL UBRR0L -#    define UCSRnA UCSR0A -#    define UCSRnB UCSR0B -#    define UCSRnC UCSR0C -#    define U2Xn U2X0 -#    define RXENn RXEN0 -#    define TXENn TXEN0 -#    define RXCIEn RXCIE0 -#    define UCSZn1 UCSZ01 -#    define UCSZn0 UCSZ00 -#    define UDRIEn UDRIE0 -#    define USARTn_UDRE_vect USART_UDRE_vect -#    define USARTn_RX_vect USART_RX_vect -#endif - -// These buffers may be any size from 2 to 256 bytes. -#define RX_BUFFER_SIZE 64 -#define TX_BUFFER_SIZE 256 - -static volatile uint8_t tx_buffer[TX_BUFFER_SIZE]; -static volatile uint8_t tx_buffer_head; -static volatile uint8_t tx_buffer_tail; -static volatile uint8_t rx_buffer[RX_BUFFER_SIZE]; -static volatile uint8_t rx_buffer_head; -static volatile uint8_t rx_buffer_tail; - -// Initialize the UART -void uart_init(uint32_t baud) { -    cli(); -    UBRRnL         = (F_CPU / 4 / baud - 1) / 2; -    UCSRnA         = (1 << U2Xn); -    UCSRnB         = (1 << RXENn) | (1 << TXENn) | (1 << RXCIEn); -    UCSRnC         = (1 << UCSZn1) | (1 << UCSZn0); -    tx_buffer_head = tx_buffer_tail = 0; -    rx_buffer_head = rx_buffer_tail = 0; -    sei(); -} - -// Transmit a byte -void uart_putchar(uint8_t c) { -    uint8_t i; - -    i = tx_buffer_head + 1; -    if (i >= TX_BUFFER_SIZE) i = 0; -    // return immediately to avoid deadlock when interrupt is disabled(called from ISR) -    if (tx_buffer_tail == i && (SREG & (1 << SREG_I)) == 0) return; -    while (tx_buffer_tail == i) -        ;  // wait until space in buffer -    // cli(); -    tx_buffer[i]   = c; -    tx_buffer_head = i; -    UCSRnB         = (1 << RXENn) | (1 << TXENn) | (1 << RXCIEn) | (1 << UDRIEn); -    // sei(); -} - -// Receive a byte -uint8_t uart_getchar(void) { -    uint8_t c, i; - -    while (rx_buffer_head == rx_buffer_tail) -        ;  // wait for character -    i = rx_buffer_tail + 1; -    if (i >= RX_BUFFER_SIZE) i = 0; -    c              = rx_buffer[i]; -    rx_buffer_tail = i; -    return c; -} - -// Return whether the number of bytes waiting in the receive buffer is nonzero. -// Call this before uart_getchar() to check if it will need -// to wait for a byte to arrive. -bool uart_available(void) { -    uint8_t head, tail; - -    head = rx_buffer_head; -    tail = rx_buffer_tail; -    if (head >= tail) return (head - tail) > 0; -    return (RX_BUFFER_SIZE + head - tail) > 0; -} - -// Transmit Interrupt -ISR(USARTn_UDRE_vect) { -    uint8_t i; - -    if (tx_buffer_head == tx_buffer_tail) { -        // buffer is empty, disable transmit interrupt -        UCSRnB = (1 << RXENn) | (1 << TXENn) | (1 << RXCIEn); -    } else { -        i = tx_buffer_tail + 1; -        if (i >= TX_BUFFER_SIZE) i = 0; -        UDRn           = tx_buffer[i]; -        tx_buffer_tail = i; -    } -} - -// Receive Interrupt -ISR(USARTn_RX_vect) { -    uint8_t c, i; - -    c = UDRn; -    i = rx_buffer_head + 1; -    if (i >= RX_BUFFER_SIZE) i = 0; -    if (i != rx_buffer_tail) { -        rx_buffer[i]   = c; -        rx_buffer_head = i; -    } -} | 
