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