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-rw-r--r--drivers/avr/uart.c170
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;
- }
-}