Control register 2
| SADD0 | Slave address bit 0 |
| SADD1_7 | Slave address bit 7_1 |
| SADD8_9 | Slave address bit 8_9 |
| RD_WRN | Transfer direction |
| ADD10 | 10-bit addressing mode |
| HEAD10R | 10-bit address header only read direction |
| START | Start generation |
| STOP | Stop generation |
| NACK | NACK generation |
| NBYTES | Number of bytes |
| RELOAD | NBYTES reload mode |
| AUTOEND | Automatic end mode |
| PECBYTE | Packet error checking byte |