Serial AFIFO configure register
| SERIAL_IN_AFIFO_RESET_WR | Write 1 to reset CDC_ACM IN async FIFO write clock domain. |
| SERIAL_IN_AFIFO_RESET_RD | Write 1 to reset CDC_ACM IN async FIFO read clock domain. |
| SERIAL_OUT_AFIFO_RESET_WR | Write 1 to reset CDC_ACM OUT async FIFO write clock domain. |
| SERIAL_OUT_AFIFO_RESET_RD | Write 1 to reset CDC_ACM OUT async FIFO read clock domain. |
| SERIAL_OUT_AFIFO_REMPTY | CDC_ACM OUTOUT async FIFO empty signal in read clock domain. |
| SERIAL_IN_AFIFO_WFULL | CDC_ACM OUT IN async FIFO empty signal in write clock domain. |