mirror of
https://github.com/arduino/Arduino.git
synced 2024-12-12 23:08:52 +01:00
213 lines
4.6 KiB
C
213 lines
4.6 KiB
C
|
/*
|
||
|
wiring_serial.c - serial functions.
|
||
|
Part of Arduino - http://www.arduino.cc/
|
||
|
|
||
|
Copyright (c) 2005-2006 David A. Mellis
|
||
|
|
||
|
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., 59 Temple Place, Suite 330,
|
||
|
Boston, MA 02111-1307 USA
|
||
|
|
||
|
$Id: wiring.c 248 2007-02-03 15:36:30Z mellis $
|
||
|
*/
|
||
|
|
||
|
#include "wiring_private.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
|
||
|
|
||
|
unsigned char rx_buffer[RX_BUFFER_SIZE];
|
||
|
|
||
|
int rx_buffer_head = 0;
|
||
|
int rx_buffer_tail = 0;
|
||
|
|
||
|
void beginSerial(long baud)
|
||
|
{
|
||
|
#if defined(__AVR_ATmega168__)
|
||
|
UBRR0H = ((F_CPU / 16 + baud / 2) / baud - 1) >> 8;
|
||
|
UBRR0L = ((F_CPU / 16 + baud / 2) / baud - 1);
|
||
|
|
||
|
// enable rx and tx
|
||
|
sbi(UCSR0B, RXEN0);
|
||
|
sbi(UCSR0B, TXEN0);
|
||
|
|
||
|
// enable interrupt on complete reception of a byte
|
||
|
sbi(UCSR0B, RXCIE0);
|
||
|
#else
|
||
|
UBRRH = ((F_CPU / 16 + baud / 2) / baud - 1) >> 8;
|
||
|
UBRRL = ((F_CPU / 16 + baud / 2) / baud - 1);
|
||
|
|
||
|
// enable rx and tx
|
||
|
sbi(UCSRB, RXEN);
|
||
|
sbi(UCSRB, TXEN);
|
||
|
|
||
|
// enable interrupt on complete reception of a byte
|
||
|
sbi(UCSRB, RXCIE);
|
||
|
#endif
|
||
|
|
||
|
// defaults to 8-bit, no parity, 1 stop bit
|
||
|
}
|
||
|
|
||
|
void serialWrite(unsigned char c)
|
||
|
{
|
||
|
#if defined(__AVR_ATmega168__)
|
||
|
while (!(UCSR0A & (1 << UDRE0)))
|
||
|
;
|
||
|
|
||
|
UDR0 = c;
|
||
|
#else
|
||
|
while (!(UCSRA & (1 << UDRE)))
|
||
|
;
|
||
|
|
||
|
UDR = c;
|
||
|
#endif
|
||
|
}
|
||
|
|
||
|
int serialAvailable()
|
||
|
{
|
||
|
return (RX_BUFFER_SIZE + rx_buffer_head - rx_buffer_tail) % RX_BUFFER_SIZE;
|
||
|
}
|
||
|
|
||
|
int serialRead()
|
||
|
{
|
||
|
// 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[rx_buffer_tail];
|
||
|
rx_buffer_tail = (rx_buffer_tail + 1) % RX_BUFFER_SIZE;
|
||
|
return c;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
void serialFlush()
|
||
|
{
|
||
|
// 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;
|
||
|
}
|
||
|
|
||
|
#if defined(__AVR_ATmega168__)
|
||
|
SIGNAL(SIG_USART_RECV)
|
||
|
#else
|
||
|
SIGNAL(SIG_UART_RECV)
|
||
|
#endif
|
||
|
{
|
||
|
#if defined(__AVR_ATmega168__)
|
||
|
unsigned char c = UDR0;
|
||
|
#else
|
||
|
unsigned char c = UDR;
|
||
|
#endif
|
||
|
|
||
|
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[rx_buffer_head] = c;
|
||
|
rx_buffer_head = i;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
void printMode(int mode)
|
||
|
{
|
||
|
// do nothing, we only support serial printing, not lcd.
|
||
|
}
|
||
|
|
||
|
void printByte(unsigned char c)
|
||
|
{
|
||
|
serialWrite(c);
|
||
|
}
|
||
|
|
||
|
void printNewline()
|
||
|
{
|
||
|
printByte('\n');
|
||
|
}
|
||
|
|
||
|
void printString(char *s)
|
||
|
{
|
||
|
while (*s)
|
||
|
printByte(*s++);
|
||
|
}
|
||
|
|
||
|
void printIntegerInBase(unsigned long n, unsigned long base)
|
||
|
{
|
||
|
unsigned char buf[8 * sizeof(long)]; // Assumes 8-bit chars.
|
||
|
unsigned long i = 0;
|
||
|
|
||
|
if (n == 0) {
|
||
|
printByte('0');
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
while (n > 0) {
|
||
|
buf[i++] = n % base;
|
||
|
n /= base;
|
||
|
}
|
||
|
|
||
|
for (; i > 0; i--)
|
||
|
printByte(buf[i - 1] < 10 ?
|
||
|
'0' + buf[i - 1] :
|
||
|
'A' + buf[i - 1] - 10);
|
||
|
}
|
||
|
|
||
|
void printInteger(long n)
|
||
|
{
|
||
|
if (n < 0) {
|
||
|
printByte('-');
|
||
|
n = -n;
|
||
|
}
|
||
|
|
||
|
printIntegerInBase(n, 10);
|
||
|
}
|
||
|
|
||
|
void printHex(unsigned long n)
|
||
|
{
|
||
|
printIntegerInBase(n, 16);
|
||
|
}
|
||
|
|
||
|
void printOctal(unsigned long n)
|
||
|
{
|
||
|
printIntegerInBase(n, 8);
|
||
|
}
|
||
|
|
||
|
void printBinary(unsigned long n)
|
||
|
{
|
||
|
printIntegerInBase(n, 2);
|
||
|
}
|
||
|
|
||
|
/* Including print() adds approximately 1500 bytes to the binary size,
|
||
|
* so we replace it with the smaller and less-confusing printString(),
|
||
|
* printInteger(), etc.
|
||
|
void print(const char *format, ...)
|
||
|
{
|
||
|
char buf[256];
|
||
|
va_list ap;
|
||
|
|
||
|
va_start(ap, format);
|
||
|
vsnprintf(buf, 256, format, ap);
|
||
|
va_end(ap);
|
||
|
|
||
|
printString(buf);
|
||
|
}
|
||
|
*/
|