/*!
* \brief Initialize TWI interface.
*
* The specified slave address is used only, if the local system
* is running as a slave. Anyway, care must be taken that it doesn't
* conflict with another connected device.
*
* \note This function is only available on ATmega128 systems.
*
* \param sla Slave address, must be specified as a 7-bit address,
* always lower than 128.
*/
int TwInit(u_char sla)
{
#ifndef __AVR_ENHANCED__
return -1;
#else
u_long speed = 2400;
if (NutRegisterIrqHandler(&sig_2WIRE_SERIAL, TwInterrupt, 0)) {
return -1;
}
/*
* Set address register, enable general call address, set transfer
* speed and enable interface.
*/
outb(TWAR, (sla << 1) | 1);
TwIOCtl(TWI_SETSPEED, &speed);
outb(TWCR, _BV(TWINT));
outb(TWCR, _BV(TWEN) | _BV(TWIE));
/*
* Initialize mutex semaphores.
*/
NutEventPost(&tw_mm_mutex);
return 0;
#endif /* __AVR_ENHANCED__ */
}
void initI2C(void) {
static uint8_t runOnce = 0;
if (!runOnce) {
runOnce = 1;
u_long baud = 100000;
TwInit(0);
TwIOCtl(TWI_SETSPEED, &baud);
DDRD &= ~( _BV(PD0) | _BV(PD1));
PORTD |= _BV(PD0) | _BV(PD1);
}
}
/* The speed of our happy I2C bus */
static const int i2c_speed = 2400;
static u_char myaddr = 0; /* ??? What address do I use? */
void i2c_init() {
log(1, "i2c_init()");
/* Set the port high first, or it won't work... is this a bug? */
outb(PORTD, 1); /* or 0xff */
/* Initialize TWI/I2C interface */
TwInit(myaddr);
/* Set the bus speed to the correct speed.... */
TwIOCtl(TWI_SETSPEED, (void *)&i2c_speed);
i2c_findslaves();
//i2c_start_threads();
}
