diff options
author | Cristian Maglie <c.maglie@bug.st> | 2013-05-17 11:02:00 +0200 |
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committer | Cristian Maglie <c.maglie@bug.st> | 2013-05-17 11:02:00 +0200 |
commit | ef4e8c65373f531ce6d37ff226a21fc9b358ff29 (patch) | |
tree | 532bf0cc782cd8342e055e763863c0ad5026d569 /cores/robot/HardwareSerial.cpp | |
parent | 44c5dae865da1f92bb183552c7e72185dd83f4f4 (diff) |
Robot has its own core
Diffstat (limited to 'cores/robot/HardwareSerial.cpp')
-rw-r--r-- | cores/robot/HardwareSerial.cpp | 508 |
1 files changed, 508 insertions, 0 deletions
diff --git a/cores/robot/HardwareSerial.cpp b/cores/robot/HardwareSerial.cpp new file mode 100644 index 0000000..eb2365f --- /dev/null +++ b/cores/robot/HardwareSerial.cpp @@ -0,0 +1,508 @@ +/* + 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 + Modified 28 September 2010 by Mark Sproul + Modified 14 August 2012 by Alarus +*/ + +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <inttypes.h> +#include "Arduino.h" +#include "wiring_private.h" + +// this next line disables the entire HardwareSerial.cpp, +// this is so I can support Attiny series and any other chip without a uart +#if defined(UBRRH) || defined(UBRR0H) || defined(UBRR1H) || defined(UBRR2H) || defined(UBRR3H) + +#include "HardwareSerial.h" + +/* + * on ATmega8, the uart and its bits are not numbered, so there is no "TXC0" + * definition. + */ +#if !defined(TXC0) +#if defined(TXC) +#define TXC0 TXC +#elif defined(TXC1) +// Some devices have uart1 but no uart0 +#define TXC0 TXC1 +#else +#error TXC0 not definable in HardwareSerial.h +#endif +#endif + +// Define constants and variables for buffering incoming serial data. We're +// using a ring buffer (I think), in which head is the index of the location +// to which to write the next incoming character and tail is the index of the +// location from which to read. +#if (RAMEND < 1000) + #define SERIAL_BUFFER_SIZE 16 +#else + #define SERIAL_BUFFER_SIZE 64 +#endif + +struct ring_buffer +{ + unsigned char buffer[SERIAL_BUFFER_SIZE]; + volatile unsigned int head; + volatile unsigned int tail; +}; + +#if defined(USBCON) + ring_buffer rx_buffer = { { 0 }, 0, 0}; + ring_buffer tx_buffer = { { 0 }, 0, 0}; +#endif +#if defined(UBRRH) || defined(UBRR0H) + ring_buffer rx_buffer = { { 0 }, 0, 0 }; + ring_buffer tx_buffer = { { 0 }, 0, 0 }; +#endif +#if defined(UBRR1H) + ring_buffer rx_buffer1 = { { 0 }, 0, 0 }; + ring_buffer tx_buffer1 = { { 0 }, 0, 0 }; +#endif +#if defined(UBRR2H) + ring_buffer rx_buffer2 = { { 0 }, 0, 0 }; + ring_buffer tx_buffer2 = { { 0 }, 0, 0 }; +#endif +#if defined(UBRR3H) + ring_buffer rx_buffer3 = { { 0 }, 0, 0 }; + ring_buffer tx_buffer3 = { { 0 }, 0, 0 }; +#endif + +inline void store_char(unsigned char c, ring_buffer *buffer) +{ + int i = (unsigned int)(buffer->head + 1) % SERIAL_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 != buffer->tail) { + buffer->buffer[buffer->head] = c; + buffer->head = i; + } +} + +#if !defined(USART0_RX_vect) && defined(USART1_RX_vect) +// do nothing - on the 32u4 the first USART is USART1 +#else +#if !defined(USART_RX_vect) && !defined(USART0_RX_vect) && \ + !defined(USART_RXC_vect) + #error "Don't know what the Data Received vector is called for the first UART" +#else + void serialEvent() __attribute__((weak)); + void serialEvent() {} + #define serialEvent_implemented +#if defined(USART_RX_vect) + ISR(USART_RX_vect) +#elif defined(USART0_RX_vect) + ISR(USART0_RX_vect) +#elif defined(USART_RXC_vect) + ISR(USART_RXC_vect) // ATmega8 +#endif + { + #if defined(UDR0) + if (bit_is_clear(UCSR0A, UPE0)) { + unsigned char c = UDR0; + store_char(c, &rx_buffer); + } else { + unsigned char c = UDR0; + }; + #elif defined(UDR) + if (bit_is_clear(UCSRA, PE)) { + unsigned char c = UDR; + store_char(c, &rx_buffer); + } else { + unsigned char c = UDR; + }; + #else + #error UDR not defined + #endif + } +#endif +#endif + +#if defined(USART1_RX_vect) + void serialEvent1() __attribute__((weak)); + void serialEvent1() {} + #define serialEvent1_implemented + ISR(USART1_RX_vect) + { + if (bit_is_clear(UCSR1A, UPE1)) { + unsigned char c = UDR1; + store_char(c, &rx_buffer1); + } else { + unsigned char c = UDR1; + }; + } +#endif + +#if defined(USART2_RX_vect) && defined(UDR2) + void serialEvent2() __attribute__((weak)); + void serialEvent2() {} + #define serialEvent2_implemented + ISR(USART2_RX_vect) + { + if (bit_is_clear(UCSR2A, UPE2)) { + unsigned char c = UDR2; + store_char(c, &rx_buffer2); + } else { + unsigned char c = UDR2; + }; + } +#endif + +#if defined(USART3_RX_vect) && defined(UDR3) + void serialEvent3() __attribute__((weak)); + void serialEvent3() {} + #define serialEvent3_implemented + ISR(USART3_RX_vect) + { + if (bit_is_clear(UCSR3A, UPE3)) { + unsigned char c = UDR3; + store_char(c, &rx_buffer3); + } else { + unsigned char c = UDR3; + }; + } +#endif + +void serialEventRun(void) +{ +#ifdef serialEvent_implemented + if (Serial.available()) serialEvent(); +#endif +#ifdef serialEvent1_implemented + if (Serial1.available()) serialEvent1(); +#endif +#ifdef serialEvent2_implemented + if (Serial2.available()) serialEvent2(); +#endif +#ifdef serialEvent3_implemented + if (Serial3.available()) serialEvent3(); +#endif +} + + +#if !defined(USART0_UDRE_vect) && defined(USART1_UDRE_vect) +// do nothing - on the 32u4 the first USART is USART1 +#else +#if !defined(UART0_UDRE_vect) && !defined(UART_UDRE_vect) && !defined(USART0_UDRE_vect) && !defined(USART_UDRE_vect) + #error "Don't know what the Data Register Empty vector is called for the first UART" +#else +#if defined(UART0_UDRE_vect) +ISR(UART0_UDRE_vect) +#elif defined(UART_UDRE_vect) +ISR(UART_UDRE_vect) +#elif defined(USART0_UDRE_vect) +ISR(USART0_UDRE_vect) +#elif defined(USART_UDRE_vect) +ISR(USART_UDRE_vect) +#endif +{ + if (tx_buffer.head == tx_buffer.tail) { + // Buffer empty, so disable interrupts +#if defined(UCSR0B) + cbi(UCSR0B, UDRIE0); +#else + cbi(UCSRB, UDRIE); +#endif + } + else { + // There is more data in the output buffer. Send the next byte + unsigned char c = tx_buffer.buffer[tx_buffer.tail]; + tx_buffer.tail = (tx_buffer.tail + 1) % SERIAL_BUFFER_SIZE; + + #if defined(UDR0) + UDR0 = c; + #elif defined(UDR) + UDR = c; + #else + #error UDR not defined + #endif + } +} +#endif +#endif + +#ifdef USART1_UDRE_vect +ISR(USART1_UDRE_vect) +{ + if (tx_buffer1.head == tx_buffer1.tail) { + // Buffer empty, so disable interrupts + cbi(UCSR1B, UDRIE1); + } + else { + // There is more data in the output buffer. Send the next byte + unsigned char c = tx_buffer1.buffer[tx_buffer1.tail]; + tx_buffer1.tail = (tx_buffer1.tail + 1) % SERIAL_BUFFER_SIZE; + + UDR1 = c; + } +} +#endif + +#ifdef USART2_UDRE_vect +ISR(USART2_UDRE_vect) +{ + if (tx_buffer2.head == tx_buffer2.tail) { + // Buffer empty, so disable interrupts + cbi(UCSR2B, UDRIE2); + } + else { + // There is more data in the output buffer. Send the next byte + unsigned char c = tx_buffer2.buffer[tx_buffer2.tail]; + tx_buffer2.tail = (tx_buffer2.tail + 1) % SERIAL_BUFFER_SIZE; + + UDR2 = c; + } +} +#endif + +#ifdef USART3_UDRE_vect +ISR(USART3_UDRE_vect) +{ + if (tx_buffer3.head == tx_buffer3.tail) { + // Buffer empty, so disable interrupts + cbi(UCSR3B, UDRIE3); + } + else { + // There is more data in the output buffer. Send the next byte + unsigned char c = tx_buffer3.buffer[tx_buffer3.tail]; + tx_buffer3.tail = (tx_buffer3.tail + 1) % SERIAL_BUFFER_SIZE; + + UDR3 = c; + } +} +#endif + + +// Constructors //////////////////////////////////////////////////////////////// + +HardwareSerial::HardwareSerial(ring_buffer *rx_buffer, ring_buffer *tx_buffer, + volatile uint8_t *ubrrh, volatile uint8_t *ubrrl, + volatile uint8_t *ucsra, volatile uint8_t *ucsrb, + volatile uint8_t *ucsrc, volatile uint8_t *udr, + uint8_t rxen, uint8_t txen, uint8_t rxcie, uint8_t udrie, uint8_t u2x) +{ + _rx_buffer = rx_buffer; + _tx_buffer = tx_buffer; + _ubrrh = ubrrh; + _ubrrl = ubrrl; + _ucsra = ucsra; + _ucsrb = ucsrb; + _ucsrc = ucsrc; + _udr = udr; + _rxen = rxen; + _txen = txen; + _rxcie = rxcie; + _udrie = udrie; + _u2x = u2x; +} + +// Public Methods ////////////////////////////////////////////////////////////// + +void HardwareSerial::begin(unsigned long baud) +{ + uint16_t baud_setting; + bool use_u2x = true; + +#if F_CPU == 16000000UL + // hardcoded exception for compatibility with the bootloader shipped + // with the Duemilanove and previous boards and the firmware on the 8U2 + // on the Uno and Mega 2560. + if (baud == 57600) { + use_u2x = false; + } +#endif + +try_again: + + 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; + } + + if ((baud_setting > 4095) && use_u2x) + { + use_u2x = false; + goto try_again; + } + + // assign the baud_setting, a.k.a. ubbr (USART Baud Rate Register) + *_ubrrh = baud_setting >> 8; + *_ubrrl = baud_setting; + + transmitting = false; + + sbi(*_ucsrb, _rxen); + sbi(*_ucsrb, _txen); + sbi(*_ucsrb, _rxcie); + cbi(*_ucsrb, _udrie); +} + +void HardwareSerial::begin(unsigned long baud, byte config) +{ + uint16_t baud_setting; + uint8_t current_config; + bool use_u2x = true; + +#if F_CPU == 16000000UL + // hardcoded exception for compatibility with the bootloader shipped + // with the Duemilanove and previous boards and the firmware on the 8U2 + // on the Uno and Mega 2560. + if (baud == 57600) { + use_u2x = false; + } +#endif + +try_again: + + 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; + } + + if ((baud_setting > 4095) && use_u2x) + { + use_u2x = false; + goto try_again; + } + + // assign the baud_setting, a.k.a. ubbr (USART Baud Rate Register) + *_ubrrh = baud_setting >> 8; + *_ubrrl = baud_setting; + + //set the data bits, parity, and stop bits +#if defined(__AVR_ATmega8__) + config |= 0x80; // select UCSRC register (shared with UBRRH) +#endif + *_ucsrc = config; + + sbi(*_ucsrb, _rxen); + sbi(*_ucsrb, _txen); + sbi(*_ucsrb, _rxcie); + cbi(*_ucsrb, _udrie); +} + +void HardwareSerial::end() +{ + // wait for transmission of outgoing data + while (_tx_buffer->head != _tx_buffer->tail) + ; + + cbi(*_ucsrb, _rxen); + cbi(*_ucsrb, _txen); + cbi(*_ucsrb, _rxcie); + cbi(*_ucsrb, _udrie); + + // clear any received data + _rx_buffer->head = _rx_buffer->tail; +} + +int HardwareSerial::available(void) +{ + return (unsigned int)(SERIAL_BUFFER_SIZE + _rx_buffer->head - _rx_buffer->tail) % SERIAL_BUFFER_SIZE; +} + +int HardwareSerial::peek(void) +{ + if (_rx_buffer->head == _rx_buffer->tail) { + return -1; + } else { + return _rx_buffer->buffer[_rx_buffer->tail]; + } +} + +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 = (unsigned int)(_rx_buffer->tail + 1) % SERIAL_BUFFER_SIZE; + return c; + } +} + +void HardwareSerial::flush() +{ + // UDR is kept full while the buffer is not empty, so TXC triggers when EMPTY && SENT + while (transmitting && ! (*_ucsra & _BV(TXC0))); + transmitting = false; +} + +size_t HardwareSerial::write(uint8_t c) +{ + int i = (_tx_buffer->head + 1) % SERIAL_BUFFER_SIZE; + + // If the output buffer is full, there's nothing for it other than to + // wait for the interrupt handler to empty it a bit + // ???: return 0 here instead? + while (i == _tx_buffer->tail) + ; + + _tx_buffer->buffer[_tx_buffer->head] = c; + _tx_buffer->head = i; + + sbi(*_ucsrb, _udrie); + // clear the TXC bit -- "can be cleared by writing a one to its bit location" + transmitting = true; + sbi(*_ucsra, TXC0); + + return 1; +} + +HardwareSerial::operator bool() { + return true; +} + +// Preinstantiate Objects ////////////////////////////////////////////////////// + +#if defined(UBRRH) && defined(UBRRL) + HardwareSerial Serial(&rx_buffer, &tx_buffer, &UBRRH, &UBRRL, &UCSRA, &UCSRB, &UCSRC, &UDR, RXEN, TXEN, RXCIE, UDRIE, U2X); +#elif defined(UBRR0H) && defined(UBRR0L) + HardwareSerial Serial(&rx_buffer, &tx_buffer, &UBRR0H, &UBRR0L, &UCSR0A, &UCSR0B, &UCSR0C, &UDR0, RXEN0, TXEN0, RXCIE0, UDRIE0, U2X0); +#elif defined(USBCON) + // do nothing - Serial object and buffers are initialized in CDC code +#else + #error no serial port defined (port 0) +#endif + +#if defined(UBRR1H) + HardwareSerial Serial1(&rx_buffer1, &tx_buffer1, &UBRR1H, &UBRR1L, &UCSR1A, &UCSR1B, &UCSR1C, &UDR1, RXEN1, TXEN1, RXCIE1, UDRIE1, U2X1); +#endif +#if defined(UBRR2H) + HardwareSerial Serial2(&rx_buffer2, &tx_buffer2, &UBRR2H, &UBRR2L, &UCSR2A, &UCSR2B, &UCSR2C, &UDR2, RXEN2, TXEN2, RXCIE2, UDRIE2, U2X2); +#endif +#if defined(UBRR3H) + HardwareSerial Serial3(&rx_buffer3, &tx_buffer3, &UBRR3H, &UBRR3L, &UCSR3A, &UCSR3B, &UCSR3C, &UDR3, RXEN3, TXEN3, RXCIE3, UDRIE3, U2X3); +#endif + +#endif // whole file + |