inline int i2c_start(i2c_t *obj) { int status = 0; int isInterrupted = I2C_CONSET(obj) & (1 << 3); // 8.1 Before master mode can be entered, I2CON must be initialised to: // - I2EN STA STO SI AA - - // - 1 0 0 x x - - // if AA = 0, it can't enter slave mode i2c_conclr(obj, 1, 1, 0, 1); // The master mode may now be entered by setting the STA bit // this will generate a start condition when the bus becomes free i2c_conset(obj, 1, 0, 0, 1); // Clearing SI bit when it wasn't set on entry can jump past state // 0x10 or 0x08 and erroneously send uninitialized slave address. if (isInterrupted) i2c_clear_SI(obj); i2c_wait_SI(obj); status = i2c_status(obj); // Clear start bit now that it's transmitted i2c_conclr(obj, 1, 0, 0, 0); return status; }
void i2c_slave_mode(i2c_t *obj, int enable_slave) { if (enable_slave != 0) { i2c_conclr(obj, 1, 1, 1, 0); i2c_conset(obj, 0, 0, 0, 1); } else { i2c_conclr(obj, 1, 1, 1, 1); } }
inline void i2c_stop(i2c_t *obj) { // write the stop bit i2c_conset(obj, 0, 1, 0, 0); i2c_clear_SI(obj); // wait for STO bit to reset while(I2C_CONSET(obj) & (1 << 4)); }
inline int i2c_stop(i2c_t *obj) { int timeout = 0; // write the stop bit i2c_conset(obj, 0, 1, 0, 0); i2c_clear_SI(obj); // wait for STO bit to reset while(I2C_CONSET(obj) & (1 << 4)) { timeout ++; if (timeout > 100000) return 1; } return 0; }
static inline int i2c_do_read(i2c_t *obj, int last) { // we are in state 0x40 (SLA+R tx'd) or 0x50 (data rx'd and ack) if(last) { i2c_conclr(obj, 0, 0, 0, 1); // send a NOT ACK } else { i2c_conset(obj, 0, 0, 0, 1); // send a ACK } // accept byte i2c_clear_SI(obj); // wait for it to arrive i2c_wait_SI(obj); // return the data return (I2C_DAT(obj) & 0xFF); }
inline int i2c_start(i2c_t *obj) { int status = 0; // 8.1 Before master mode can be entered, I2CON must be initialised to: // - I2EN STA STO SI AA - - // - 1 0 0 0 x - - // if AA = 0, it can't enter slave mode i2c_conclr(obj, 1, 1, 1, 1); // The master mode may now be entered by setting the STA bit // this will generate a start condition when the bus becomes free i2c_conset(obj, 1, 0, 0, 1); i2c_wait_SI(obj); status = i2c_status(obj); // Clear start bit now transmitted, and interrupt bit i2c_conclr(obj, 1, 0, 0, 0); return status; }