NA
| FLUSHTB | Flushes the from-bus buffer/FIFO. Not normally used |
| FLUSHFB | Flushes the to-bus buffer/FIFO. Used when Master terminates a to-bus (read) message prematurely |
| UNLOCK | If this bit is not written 1, the register bits from 7 to 4 are not changed on write. |
| TXTRIG | Trigger level for tx emptiness when FIFOed, Affects interrupt and DMA(if enabled). The defaults is 3 |
| RXTRIG | Trigger level for rx fulless when FIFOed, Affects interrupt and DMA(if enabled). The defaults is 3 |
| TXCOUNT | NA |
| RXCOUNT | NA |
| TXFULL | NA |
| RXEMPTY | NA |