| ACK_REC | This register stores the value of ACK bit. |
| SLAVE_RW | when in slave mode 1: master read slave 0: master write slave. |
| TIME_OUT | when I2C takes more than time_out_reg clocks to receive a data then this register changes to high level. |
| ARB_LOST | when I2C lost control of SDA line this register changes to high level. |
| BUS_BUSY | 1:I2C bus is busy transferring data. 0:I2C bus is in idle state. |
| SLAVE_ADDRESSED | when configured as i2c slave and the address send by master is equal to slave’s address then this bit will be high level. |
| BYTE_TRANS | This register changes to high level when one byte is transferred. |
| RXFIFO_CNT | This register represent the amount of data need to send. |
| TXFIFO_CNT | This register stores the amount of received data in ram. |
| SCL_MAIN_STATE_LAST | This register stores the value of state machine for i2c module. 3’h0: SCL_MAIN_IDLE 3’h1: SCL_ADDRESS_SHIFT 3’h2: SCL_ACK_ADDRESS 3’h3: SCL_RX_DATA 3’h4 SCL_TX_DATA 3’h5:SCL_SEND_ACK 3’h6:SCL_WAIT_ACK |
| SCL_STATE_LAST | This register stores the value of state machine to produce SCL. 3’h0: SCL_IDLE 3’h1:SCL_START 3’h2:SCL_LOW_EDGE 3’h3: SCL_LOW 3’h4:SCL_HIGH_EDGE 3’h5:SCL_HIGH 3’h6:SCL_STOP |