Scalable Scatter-Gather DMA Intel® FPGA IP User Guide

ID 823097
Date 4/07/2025
Public
Document Table of Contents

4.4.4. Host to Device <PORT#> Avalon-ST Source Interface

This interface is enabled if the Number of H2D ST Device Ports parameter is equal or more than 1 and Interface Type of Avalon-ST is selected. This interface is in little endian mode.

Clock Domain: h2d<PORT>_st_clk

Reset: h2d<PORT>_st_resetn

Table 54.  Host to Device Avalon-ST Source Interface
Signal Name Direction Description
h2d<PORT>_st_valid OUT Indicates that the source is driving a valid transfer.
h2d<PORT>_st_ready IN Indicates that the sink can accept a transfer in the current cycle.
h2d<PORT>_st_data[(H2D_ST<PORT>_DWD-1):0] OUT Data interface. H2D_ST<PORT>_DWD: 8, 16, 32, 64, 128, 256, 512, 1024
h2d<PORT>_st_sop OUT Indicates the start of packet.
h2d<PORT>_st_eop OUT Indicates the end of packet.
h2d<PORT>_st_channel[(H2D_ST<PORT>_CWD-1):0] OUT Indicate the channel to which the data belongs.

Default H2D_ST<PORT>_CWD: 1

h2d<PORT>_st_empty[log2(H2D_ST<PORT>_DWD/8)-1:0] OUT Indicates the number of bytes that are empty, i.e. invalid data. Invalid data or empty cycle is only permitted at the end of the packet transfer.
h2d<PORT>_st_error [(H2D_ST<PORT>EWD-1):0] OUT Avalon® error signal. Available when the Error Width of H2D_ST Port <PORT> parameter is configured to a value between 1 and 8. This signal is valid at the h2d<PORT>_st_eop cycle only. Default H2D_ST<PORT>_EWD: 0
Table 55.  Host to Device PTP Avalon-ST Sink Interface
Signal Name Direction Description
h2d<PORT>_st_ptp_valid IN Indicates that the source is driving a valid transfer
h2d<PORT>_st_ptp_ready OUT

Indicates that the sink can accept a transfer in the current cycle.

"readyLatency" parameter defined in Avalon spec shall be supported. By default the value is '0'.

h2d<PORT>_st_ptp_data

[95:0]

IN Data interface that carries 96-bit timestamp information.

h2d<PORT>_st_ptp_channel

[(H2D_ST<PORT>_CWD-1):0]

IN Indicates the channel to which the data belongs.
Note: Applicable only if you enable the H2D Avalon-ST Source port and PTP timestamp writeback.