Scalable Scatter-Gather DMA Intel® FPGA IP User Guide

ID 823097
Date 1/27/2025
Public
Document Table of Contents

4.2.2. Application Packet Transmit Interface

This interface presents the outbound PCIe TLP packet. Connect this interface to AXI4-Stream Transmit (TX) interface of GTS AXI Streaming Intel® FPGA IP for PCI Express.

Clock Domain: ss_axi_st_clk

Reset: ss_axi_st_aresetn

Data width of PCIe IP AXI-ST TX and RX Interface(SS_ST_DWD) = 128, 256

Table 35.  APP AXI ST TX Interface
Signal Name Direction Description
app_ss_st_tx_tvalid OUT Indicates that the source is driving a valid transfer.
ss_app_st_tx_tready IN
  • Indicates that the sink can accept a transfer in the current cycle.
  • By default, the value is '0'.

app_ss_st_tx_tdata[

(SS_ST_DWD-1):0]

OUT
  • Data interface with configurable width specified by SS_ST_DWD parameter.

app_ss_st_tx_tkeep[

(SS_ST_DWD/8-1):0]

OUT
  • A byte qualifier used to indicate whether the content of the associated byte is valid
  • The invalid bytes are allowed only during app_ss_st_tx_tlast cycle
  • The sparse app_ss_st_tx_tkeep is not allowed
app_ss_st_tx_tlast OUT Indicates End of Data/Command Transmission