Visible to Intel only — GUID: iga1432671698727
Ixiasoft
Visible to Intel only — GUID: iga1432671698727
Ixiasoft
10.4.4. fcr
Identifier | Title | Offset | Access | Reset Value | Description |
---|---|---|---|---|---|
fcr | FIFO Control | 0x8 | W | 0x00000000 | Controls FIFO operation when written. |
Bit Fields | |||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 |
- | |||||||||||||||
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
- | rt | - | dmam | xfifor | rfifor | fifoe |
Bit | Name/Identifier | Description | Access | Reset |
---|---|---|---|---|
[31:8] | - | Reserved | R | 0x0 |
[7:6] | Rx Trigger Level (rt) | This register is configured to implement FIFOs RxTrigger (or RT). This is used to select the trigger level in the receiver FIFO at which the Received Data Available Interrupt will be generated. In auto flow control mode it is used to determine when the rts_n signal will be de-asserted The following trigger levels are supported:
|
W | 0x0 |
[5:4] | - | Reserved | R | 0x0 |
[3] | DMA Mode (dmam) | This determines the DMA signaling mode used for the uart_dma_tx_req_n and uart_dma_rx_req_n output signals when additional DMA handshaking signals are not selected. DMA mode 0 supports single DMA data transfers at a time. In mode 0, the uart_dma_tx_req_n signal goes active low under the following conditions:
It goes inactive under the following conditions:
DMA mode 1 supports multi-DMA data transfers, where multiple transfers are made continuously until the receiver FIFO has been emptied or the transmit FIFO has been filled. In mode 1 the uart_dma_tx_req_n signal is asserted under the following condition:
|
W | 0x0 |
[2] | Tx FIFO Reset (xfifor) | This bit resets the control portion of the transmit FIFO and treats the FIFO as empty. Note that this bit is 'self-clearing' and it is not necessary to clear this bit. Please allow for 8 clock cycles to pass after changing this register bit before reading from RBR or writing to THR. |
W | 0x0 |
[1] | Rx FIFO Reset (rfifor) | Resets the control portion of the receive FIFO and treats the FIFO as empty. Note that this bit is self-clearing' and it is not necessary to clear this bit. Allow for 8 clock cycles to pass after changing this register bit before reading from RBR or writing to THR. |
W | 0x0 |
[0] | FIFO Enable (fifoe) | This bit enables/disables the transmit (Tx) and receive (Rx ) FIFO's. Whenever the value of this bit is changed both the Tx and Rx controller portion of FIFO's will be reset. Any existing data in both Tx and Rx FIFO will be lost when this bit is changed. Please allow for 8 clock cycles to pass after changing this register bit before reading from RBR or writing to THR. |
W | 0x0 |