void i2c_init(void) {
TWSR = 0; /* no prescaler */
TWBR = (uint8_t)TWBR_val;
+
+ #ifdef __AVR_ATmega32A__
+ // set pull-up resistors on I2C bus pins
+ PORTC |= 0b11;
+
+ // enable TWI (two-wire interface)
+ TWCR |= (1 << TWEN);
+
+ // enable TWI interrupt and slave address ACK
+ TWCR |= (1 << TWIE);
+ TWCR |= (1 << TWEA);
+ #endif
}
i2c_status_t i2c_start(uint8_t address, uint16_t timeout) {
return TWDR;
}
-i2c_status_t i2c_transmit(uint8_t address, uint8_t* data, uint16_t length, uint16_t timeout) {
+i2c_status_t i2c_transmit(uint8_t address, const uint8_t* data, uint16_t length, uint16_t timeout) {
i2c_status_t status = i2c_start(address | I2C_WRITE, timeout);
for (uint16_t i = 0; i < length && status >= 0; i++) {
return (status < 0) ? status : I2C_STATUS_SUCCESS;
}
-i2c_status_t i2c_writeReg(uint8_t devaddr, uint8_t regaddr, uint8_t* data, uint16_t length, uint16_t timeout) {
+i2c_status_t i2c_writeReg(uint8_t devaddr, uint8_t regaddr, const uint8_t* data, uint16_t length, uint16_t timeout) {
i2c_status_t status = i2c_start(devaddr | 0x00, timeout);
if (status >= 0) {
status = i2c_write(regaddr, timeout);