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Diffstat (limited to 'core/HardwareSerial.cpp')
-rwxr-xr-x | core/HardwareSerial.cpp | 219 |
1 files changed, 0 insertions, 219 deletions
diff --git a/core/HardwareSerial.cpp b/core/HardwareSerial.cpp deleted file mode 100755 index 1af6a66..0000000 --- a/core/HardwareSerial.cpp +++ /dev/null @@ -1,219 +0,0 @@ -/* - HardwareSerial.cpp - Hardware serial library for Wiring - Copyright (c) 2006 Nicholas Zambetti. All right reserved. - - This library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - This library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with this library; if not, write to the Free Software - Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - - Modified 23 November 2006 by David A. Mellis -*/ - -#include <stdio.h> -#include <string.h> -#include <inttypes.h> -#include "wiring.h" -#include "wiring_private.h" - -#include "HardwareSerial.h" - -// Define constants and variables for buffering incoming serial data. We're -// using a ring buffer (I think), in which rx_buffer_head is the index of the -// location to which to write the next incoming character and rx_buffer_tail -// is the index of the location from which to read. -#define RX_BUFFER_SIZE 128 - -struct ring_buffer { - unsigned char buffer[RX_BUFFER_SIZE]; - int head; - int tail; -}; - -ring_buffer rx_buffer = { { 0 }, 0, 0 }; - -#if defined(__AVR_ATmega1280__) -ring_buffer rx_buffer1 = { { 0 }, 0, 0 }; -ring_buffer rx_buffer2 = { { 0 }, 0, 0 }; -ring_buffer rx_buffer3 = { { 0 }, 0, 0 }; -#endif - -inline void store_char(unsigned char c, ring_buffer *rx_buffer) -{ - int i = (rx_buffer->head + 1) % RX_BUFFER_SIZE; - - // if we should be storing the received character into the location - // just before the tail (meaning that the head would advance to the - // current location of the tail), we're about to overflow the buffer - // and so we don't write the character or advance the head. - if (i != rx_buffer->tail) { - rx_buffer->buffer[rx_buffer->head] = c; - rx_buffer->head = i; - } -} - -#if defined(__AVR_ATmega1280__) - -SIGNAL(SIG_USART0_RECV) -{ - unsigned char c = UDR0; - store_char(c, &rx_buffer); -} - -SIGNAL(SIG_USART1_RECV) -{ - unsigned char c = UDR1; - store_char(c, &rx_buffer1); -} - -SIGNAL(SIG_USART2_RECV) -{ - unsigned char c = UDR2; - store_char(c, &rx_buffer2); -} - -SIGNAL(SIG_USART3_RECV) -{ - unsigned char c = UDR3; - store_char(c, &rx_buffer3); -} - -#else - -#if defined(__AVR_ATmega8__) -SIGNAL(SIG_UART_RECV) -#else -SIGNAL(USART_RX_vect) -#endif -{ -#if defined(__AVR_ATmega8__) - unsigned char c = UDR; -#else - unsigned char c = UDR0; -#endif - store_char(c, &rx_buffer); -} - -#endif - -// Constructors //////////////////////////////////////////////////////////////// - -HardwareSerial::HardwareSerial(ring_buffer *rx_buffer, - volatile uint8_t *ubrrh, volatile uint8_t *ubrrl, - volatile uint8_t *ucsra, volatile uint8_t *ucsrb, - volatile uint8_t *udr, - uint8_t rxen, uint8_t txen, uint8_t rxcie, uint8_t udre, uint8_t u2x) -{ - _rx_buffer = rx_buffer; - _ubrrh = ubrrh; - _ubrrl = ubrrl; - _ucsra = ucsra; - _ucsrb = ucsrb; - _udr = udr; - _rxen = rxen; - _txen = txen; - _rxcie = rxcie; - _udre = udre; - _u2x = u2x; -} - -// Public Methods ////////////////////////////////////////////////////////////// - -void HardwareSerial::begin(long baud) -{ - uint16_t baud_setting; - bool use_u2x; - - // U2X mode is needed for baud rates higher than (CPU Hz / 16) - if (baud > F_CPU / 16) { - use_u2x = true; - } else { - // figure out if U2X mode would allow for a better connection - - // calculate the percent difference between the baud-rate specified and - // the real baud rate for both U2X and non-U2X mode (0-255 error percent) - uint8_t nonu2x_baud_error = abs((int)(255-((F_CPU/(16*(((F_CPU/8/baud-1)/2)+1))*255)/baud))); - uint8_t u2x_baud_error = abs((int)(255-((F_CPU/(8*(((F_CPU/4/baud-1)/2)+1))*255)/baud))); - - // prefer non-U2X mode because it handles clock skew better - use_u2x = (nonu2x_baud_error > u2x_baud_error); - } - - if (use_u2x) { - *_ucsra = 1 << _u2x; - baud_setting = (F_CPU / 4 / baud - 1) / 2; - } else { - *_ucsra = 0; - baud_setting = (F_CPU / 8 / baud - 1) / 2; - } - - // assign the baud_setting, a.k.a. ubbr (USART Baud Rate Register) - *_ubrrh = baud_setting >> 8; - *_ubrrl = baud_setting; - - sbi(*_ucsrb, _rxen); - sbi(*_ucsrb, _txen); - sbi(*_ucsrb, _rxcie); -} - -uint8_t HardwareSerial::available(void) -{ - return (RX_BUFFER_SIZE + _rx_buffer->head - _rx_buffer->tail) % RX_BUFFER_SIZE; -} - -int HardwareSerial::read(void) -{ - // if the head isn't ahead of the tail, we don't have any characters - if (_rx_buffer->head == _rx_buffer->tail) { - return -1; - } else { - unsigned char c = _rx_buffer->buffer[_rx_buffer->tail]; - _rx_buffer->tail = (_rx_buffer->tail + 1) % RX_BUFFER_SIZE; - return c; - } -} - -void HardwareSerial::flush() -{ - // don't reverse this or there may be problems if the RX interrupt - // occurs after reading the value of rx_buffer_head but before writing - // the value to rx_buffer_tail; the previous value of rx_buffer_head - // may be written to rx_buffer_tail, making it appear as if the buffer - // don't reverse this or there may be problems if the RX interrupt - // occurs after reading the value of rx_buffer_head but before writing - // the value to rx_buffer_tail; the previous value of rx_buffer_head - // may be written to rx_buffer_tail, making it appear as if the buffer - // were full, not empty. - _rx_buffer->head = _rx_buffer->tail; -} - -void HardwareSerial::write(uint8_t c) -{ - while (!((*_ucsra) & (1 << _udre))) - ; - - *_udr = c; -} - -// Preinstantiate Objects ////////////////////////////////////////////////////// - -#if defined(__AVR_ATmega8__) -HardwareSerial Serial(&rx_buffer, &UBRRH, &UBRRL, &UCSRA, &UCSRB, &UDR, RXEN, TXEN, RXCIE, UDRE, U2X); -#else -HardwareSerial Serial(&rx_buffer, &UBRR0H, &UBRR0L, &UCSR0A, &UCSR0B, &UDR0, RXEN0, TXEN0, RXCIE0, UDRE0, U2X0); -#endif - -#if defined(__AVR_ATmega1280__) -HardwareSerial Serial1(&rx_buffer1, &UBRR1H, &UBRR1L, &UCSR1A, &UCSR1B, &UDR1, RXEN1, TXEN1, RXCIE1, UDRE1, U2X1); -HardwareSerial Serial2(&rx_buffer2, &UBRR2H, &UBRR2L, &UCSR2A, &UCSR2B, &UDR2, RXEN2, TXEN2, RXCIE2, UDRE2, U2X2); -HardwareSerial Serial3(&rx_buffer3, &UBRR3H, &UBRR3L, &UCSR3A, &UCSR3B, &UDR3, RXEN3, TXEN3, RXCIE3, UDRE3, U2X3); -#endif |