control register 2
| DMAREN | DMA receive enable |
| DMATEN | DMA transmit enable |
| HWCSOE | Hardware CS output enable |
| TIEN | TI mode enable |
| ERRIE | Error interrupt enable |
| RDBFIE | Receive data buffer full interrupt enable |
| TDBEIE | Transmit data buffer empty interrupt enable |
| MDIV3 | Master clock frequency division bit3 |
| MDIV3EN | Master clock frequency 3 division enable |