303 lines
8.2 KiB
C++
303 lines
8.2 KiB
C++
/*
|
|
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
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <inttypes.h>
|
|
#include "wiring.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"
|
|
|
|
// 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.
|
|
#if (RAMEND < 1000)
|
|
#define RX_BUFFER_SIZE 32
|
|
#else
|
|
#define RX_BUFFER_SIZE 128
|
|
#endif
|
|
|
|
struct ring_buffer
|
|
{
|
|
unsigned char buffer[RX_BUFFER_SIZE];
|
|
int head;
|
|
int tail;
|
|
};
|
|
|
|
#if defined(UBRRH) || defined(UBRR0H)
|
|
ring_buffer rx_buffer = { { 0 }, 0, 0 };
|
|
#endif
|
|
#if defined(UBRR1H)
|
|
ring_buffer rx_buffer1 = { { 0 }, 0, 0 };
|
|
#endif
|
|
#if defined(UBRR2H)
|
|
ring_buffer rx_buffer2 = { { 0 }, 0, 0 };
|
|
#endif
|
|
#if defined(UBRR3H)
|
|
ring_buffer rx_buffer3 = { { 0 }, 0, 0 };
|
|
#endif
|
|
|
|
inline void store_char(unsigned char c, ring_buffer *rx_buffer)
|
|
{
|
|
int i = (unsigned int)(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(USART_RX_vect)
|
|
SIGNAL(USART_RX_vect)
|
|
{
|
|
#if defined(UDR0)
|
|
unsigned char c = UDR0;
|
|
#elif defined(UDR)
|
|
unsigned char c = UDR; // atmega8535
|
|
#else
|
|
#error UDR not defined
|
|
#endif
|
|
store_char(c, &rx_buffer);
|
|
}
|
|
#elif defined(SIG_USART0_RECV) && defined(UDR0)
|
|
SIGNAL(SIG_USART0_RECV)
|
|
{
|
|
unsigned char c = UDR0;
|
|
store_char(c, &rx_buffer);
|
|
}
|
|
#elif defined(SIG_UART0_RECV) && defined(UDR0)
|
|
SIGNAL(SIG_UART0_RECV)
|
|
{
|
|
unsigned char c = UDR0;
|
|
store_char(c, &rx_buffer);
|
|
}
|
|
//#elif defined(SIG_USART_RECV)
|
|
#elif defined(USART0_RX_vect)
|
|
// fixed by Mark Sproul this is on the 644/644p
|
|
//SIGNAL(SIG_USART_RECV)
|
|
SIGNAL(USART0_RX_vect)
|
|
{
|
|
#if defined(UDR0)
|
|
unsigned char c = UDR0;
|
|
#elif defined(UDR)
|
|
unsigned char c = UDR; // atmega8, atmega32
|
|
#else
|
|
#error UDR not defined
|
|
#endif
|
|
store_char(c, &rx_buffer);
|
|
}
|
|
#elif defined(SIG_UART_RECV)
|
|
// this is for atmega8
|
|
SIGNAL(SIG_UART_RECV)
|
|
{
|
|
#if defined(UDR0)
|
|
unsigned char c = UDR0; // atmega645
|
|
#elif defined(UDR)
|
|
unsigned char c = UDR; // atmega8
|
|
#endif
|
|
store_char(c, &rx_buffer);
|
|
}
|
|
#elif defined(USBCON)
|
|
#warning No interrupt handler for usart 0
|
|
#warning Serial(0) is on USB interface
|
|
#else
|
|
#error No interrupt handler for usart 0
|
|
#endif
|
|
|
|
//#if defined(SIG_USART1_RECV)
|
|
#if defined(USART1_RX_vect)
|
|
//SIGNAL(SIG_USART1_RECV)
|
|
SIGNAL(USART1_RX_vect)
|
|
{
|
|
unsigned char c = UDR1;
|
|
store_char(c, &rx_buffer1);
|
|
}
|
|
#elif defined(SIG_USART1_RECV)
|
|
#error SIG_USART1_RECV
|
|
#endif
|
|
|
|
#if defined(USART2_RX_vect) && defined(UDR2)
|
|
SIGNAL(USART2_RX_vect)
|
|
{
|
|
unsigned char c = UDR2;
|
|
store_char(c, &rx_buffer2);
|
|
}
|
|
#elif defined(SIG_USART2_RECV)
|
|
#error SIG_USART2_RECV
|
|
#endif
|
|
|
|
#if defined(USART3_RX_vect) && defined(UDR3)
|
|
SIGNAL(USART3_RX_vect)
|
|
{
|
|
unsigned char c = UDR3;
|
|
store_char(c, &rx_buffer3);
|
|
}
|
|
#elif defined(SIG_USART3_RECV)
|
|
#error SIG_USART3_RECV
|
|
#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 = 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
|
|
|
|
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);
|
|
}
|
|
|
|
void HardwareSerial::end()
|
|
{
|
|
cbi(*_ucsrb, _rxen);
|
|
cbi(*_ucsrb, _txen);
|
|
cbi(*_ucsrb, _rxcie);
|
|
}
|
|
|
|
int HardwareSerial::available(void)
|
|
{
|
|
return (unsigned int)(RX_BUFFER_SIZE + _rx_buffer->head - _rx_buffer->tail) % RX_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) % 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(UBRRH) && defined(UBRRL)
|
|
HardwareSerial Serial(&rx_buffer, &UBRRH, &UBRRL, &UCSRA, &UCSRB, &UDR, RXEN, TXEN, RXCIE, UDRE, U2X);
|
|
#elif defined(UBRR0H) && defined(UBRR0L)
|
|
HardwareSerial Serial(&rx_buffer, &UBRR0H, &UBRR0L, &UCSR0A, &UCSR0B, &UDR0, RXEN0, TXEN0, RXCIE0, UDRE0, U2X0);
|
|
#elif defined(USBCON)
|
|
#warning no serial port defined (port 0)
|
|
#else
|
|
#error no serial port defined (port 0)
|
|
#endif
|
|
|
|
#if defined(UBRR1H)
|
|
HardwareSerial Serial1(&rx_buffer1, &UBRR1H, &UBRR1L, &UCSR1A, &UCSR1B, &UDR1, RXEN1, TXEN1, RXCIE1, UDRE1, U2X1);
|
|
#endif
|
|
#if defined(UBRR2H)
|
|
HardwareSerial Serial2(&rx_buffer2, &UBRR2H, &UBRR2L, &UCSR2A, &UCSR2B, &UDR2, RXEN2, TXEN2, RXCIE2, UDRE2, U2X2);
|
|
#endif
|
|
#if defined(UBRR3H)
|
|
HardwareSerial Serial3(&rx_buffer3, &UBRR3H, &UBRR3L, &UCSR3A, &UCSR3B, &UDR3, RXEN3, TXEN3, RXCIE3, UDRE3, U2X3);
|
|
#endif
|
|
|
|
#endif // whole file
|
|
|