39 lines
876 B
C
39 lines
876 B
C
#include "i2c.h"
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void initI2C(void) {
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TWBR = 32; /* set bit rate, see p. 242 */
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/* 8MHz / (16+2*TWBR*1) ~= 100kHz */
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TWCR |= (1 << TWEN); /* enable */
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}
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void i2cWaitForComplete(void) {
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loop_until_bit_is_set(TWCR, TWINT);
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}
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void i2cStart(void) {
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TWCR = (_BV(TWINT) | _BV(TWEN) | _BV(TWSTA));
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i2cWaitForComplete();
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}
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void i2cStop(void) {
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TWCR = (_BV(TWINT) | _BV(TWEN) | _BV(TWSTO));
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}
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uint8_t i2cReadAck(void) {
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TWCR = (_BV(TWINT) | _BV(TWEN) | _BV(TWEA));
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i2cWaitForComplete();
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return (TWDR);
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}
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uint8_t i2cReadNoAck(void) {
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TWCR = (_BV(TWINT) | _BV(TWEN));
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i2cWaitForComplete();
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return (TWDR);
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}
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void i2cSend(uint8_t data) {
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TWDR = data;
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TWCR = (_BV(TWINT) | _BV(TWEN)); /* init and enable */
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i2cWaitForComplete();
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}
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