Control register 1
| I2CEN | I2C peripheral enable |
| TDIEN | Transmit data interrupt enable |
| RDIEN | Receive data interrupt enable |
| ADDRIEN | Address match interrupt enable |
| ACKFAILIEN | Acknowledge fail interrupt enable |
| STOPIEN | Stop generation complete interrupt enable |
| TDCIEN | Transfer data complete interrupt enable |
| ERRIEN | Error interrupts enable |
| DFLT | Digital filter value |
| DMATEN | DMA Transmit data request enable |
| DMAREN | DMA receive data request enable |
| SCTRL | Slave receiving data control |
| STRETCH | Clock stretching mode |
| GCAEN | General call address enable |
| HADDREN | SMBus host address enable |
| DEVADDREN | SMBus device default address enable |
| SMBALERT | SMBus alert enable / pin set |
| PECEN | PEC calculation enable |