Configures FIFO fill level that triggers interrupt and packing 1 or 2 samples per word.
| PACKED_READ | 0 = one sample is packed in one 32-bit read cycle 1 = two samples are packed in one 32-bit read cycle |
| LEVEL | When the FIFO contains more or equal than FIFO_LEVEL samples interrupt flag FIFO_FULL interrupt will be set and DMA_Read_Req will be raised. |
| RESERVED | Reserved |