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Update i2c.c

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ishtob 2017-03-22 15:50:18 -04:00 committed by GitHub
parent 092416325b
commit bb413383ee
1 changed files with 0 additions and 90 deletions
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90
keyboards/lets_split/i2c.c
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@ -161,94 +161,4 @@ ISR(TWI_vect) {
TWCR |= (1<<TWIE) | (1<<TWINT) | (ack<<TWEA) | (1<<TWEN);
}
// from SSD1306
/*
void i2c_start_wait(unsigned char address)
{
uint8_t twst;
while ( 1 )
{
// send START condition
TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
// wait until transmission completed
while(!(TWCR & (1<<TWINT)));
// check value of TWI Status Register. Mask prescaler bits.
twst = TW_STATUS & 0xF8;
if ( (twst != TW_START) && (twst != TW_REP_START)) continue;
// send device address
TWDR = address;
TWCR = (1<<TWINT) | (1<<TWEN);
// wail until transmission completed
while(!(TWCR & (1<<TWINT)));
// check value of TWI Status Register. Mask prescaler bits.
twst = TW_STATUS & 0xF8;
if ( (twst == TW_MT_SLA_NACK )||(twst ==TW_MR_DATA_NACK) )
{
// device busy, send stop condition to terminate write operation
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
// wait until stop condition is executed and bus released
while(TWCR & (1<<TWSTO));
continue;
}
//if( twst != TW_MT_SLA_ACK) return 1;
break;
}
}// i2c_start_wait
*/
/*************************************************************************
Issues a repeated start condition and sends address and transfer direction
Input: address and transfer direction of I2C device
Return: 0 device accessible
1 failed to access device
*************************************************************************/
/*
unsigned char i2c_rep_start(unsigned char address)
{
return i2c_master_start( address );
}/* i2c_rep_start */
/*************************************************************************
Read one byte from the I2C device, request more data from device
Return: byte read from I2C device
*************************************************************************/
/*
unsigned char i2c_readAck(void)
{
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
while(!(TWCR & (1<<TWINT)));
return TWDR;
}/* i2c_readAck */
/*************************************************************************
Read one byte from the I2C device, read is followed by a stop condition
Return: byte read from I2C device
*************************************************************************
unsigned char i2c_readNak(void)
{
TWCR = (1<<TWINT) | (1<<TWEN);
while(!(TWCR & (1<<TWINT)));
return TWDR;
}/* i2c_readNak */
#endif