F-Tile Serial Lite IV Intel® FPGA IP Design Example User Guide

ID 683287
Date 12/13/2021
Public

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3.2.3. DCFIFO

The design uses two DCFIFO blocks at both TX and RX paths. The DCFIFO blocks handle data streaming and control signals for clock crossing between different clock domains.

Table 8.  TX and RX DCFIFO Configuration
Parameter Value
lpm_width (Number of lanes x 64)+32
lpm_numwords 64

The format of the data that transmits through the FIFO is similar to the format generated by the traffic generator.

Figure 7. Data Format
Table 9.  Control SignalsThe table lists how the IP concatenates the TX and RX control signals with the data bus signals and passes through the data.
Control DCFIFO Data Out Bit Signal Description
[20]

tx_valid

rx_valid

Indicates TX or RX data is valid for Full and Basic modes.

[19]

tx_start_of_packet

rx_start_of_packet

Indicates the start of a TX or RX data packet.

For Full mode only.

[18]

tx_end_of_packet

rx_end_of_packet

Indicates the end of a TX or RX data packet.

For Full mode only.

[17:10]

tx_channel

rx_channel

The channel number for data being transmitted or received on the current cycle number.

For Full mode only.

[9:5]

tx_empty

rx_empty

Indicates the number of non-valid words in the final burst of the TX or RX data.

For Full mode only.

[4:1]

tg_tx_num_valid_bytes_eob

tc_rx_num_valid_bytes_eob

Indicates the number of valid bytes in the last word of the final burst.

For Full mode only.

[0]

tg_tx_is_usr_cmd

tc_rx_is_usr_cmd

Initiates a user-defined information cycle.

  • Full mode: Must coincide with tx_startofpacket or rx_startofpacket
  • Basic mode: Not supported.