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Added OLED SSD1306 support to I2C

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ishtob 2017-03-22 15:04:11 -04:00 • committed by GitHub
parent 423c68c210
commit 65317a3a02
8 changed files with 908 additions and 21 deletions
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94
keyboards/lets_split/i2c.c
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@ -48,7 +48,7 @@ void i2c_master_init(void) {
// returns: 0 => success
// 1 => error
uint8_t i2c_master_start(uint8_t address) {
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTA);
TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
i2c_delay();
@ -56,6 +56,7 @@ uint8_t i2c_master_start(uint8_t address) {
if ( (TW_STATUS != TW_START) && (TW_STATUS != TW_REP_START))
return 1;
// send device address
TWDR = address;
TWCR = (1<<TWINT) | (1<<TWEN);
@ -159,4 +160,95 @@ ISR(TWI_vect) {
// Reset everything, so we are ready for the next TWI interrupt
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