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Use SDA and SCL constants, not hardcoded registers for TWI pullups.

http://code.google.com/p/arduino/issues/detail?id=601
This commit is contained in:
David A. Mellis 2011-09-08 16:50:07 -04:00
parent 7d8d20894c
commit 71289521bf

View File

@ -32,6 +32,7 @@
#define sbi(sfr, bit) (_SFR_BYTE(sfr) |= _BV(bit))
#endif
#include "pins_arduino.h"
#include "twi.h"
static volatile uint8_t twi_state;
@ -63,18 +64,10 @@ void twi_init(void)
{
// initialize state
twi_state = TWI_READY;
#if defined(__AVR_ATmega168__) || defined(__AVR_ATmega8__) || defined(__AVR_ATmega328P__)
// activate internal pull-ups for twi
// as per note from atmega8 manual pg167
sbi(PORTC, 4);
sbi(PORTC, 5);
#else
// activate internal pull-ups for twi
// as per note from atmega128 manual pg204
sbi(PORTD, 0);
sbi(PORTD, 1);
#endif
// activate internal pullups for twi.
digitalWrite(SDA, 1);
digitalWrite(SCL, 1);
// initialize twi prescaler and bit rate
cbi(TWSR, TWPS0);