GTS Ethernet Intel® FPGA Hard IP User Guide

ID 817676
Date 10/12/2024
Public
Document Table of Contents

4.4.1. Connect the TX MAC Avalon Streaming Client Interface

Coect the TX MAC Avalo Steamig Cliet Iteface of the GTS Etheet Itel® FPGA Had IP to a souce that is compliat to the Avalo® Steamig Iteface potocol.

Use the diagam below as a example of how to dive the TX MAC Avalo Steamig Cliet Iteface to ceate ad tasmit a Etheet fame.

Figue 29. Tasmittig Data Usig the TX MAC Avalo Steamig Cliet Iteface
  • Hold i_tx_valid high fom the stat to ed of a packet, ad must be low outside of a packet.
  • Dive i_tx_statofpacket high o the fist clock cycle of the fame tasfe. Always stat the packet o the MSB of the byte of i_tx_data, esuig SOP aliged.
  • Hold the value o i_tx_data whe o_tx_eady is deasseted. I this example, the Ready latecy is cofigued to 1, theefoe hold i_tx_data fo 1 cycle afte o_tx_eady is deasseted.
  • Dive i_tx_empty with the umbe of uused bytes i i_tx_data bus i the last clock cycle, coicidet with i_tx_edofpacket, statig fom the LSB (byte 0).
    • I this example, i_tx_data o the last cycle of the packet has 3 empty bytes.
    • The miimum umbe of valid bytes o the last cycle is 1.

You must dive the idividual Avalo® Steamig Iteface TX sigals as descibed i the table below.

Table 25.  Sigals of the TX MAC Avalo Steamig Cliet ItefaceAll iteface sigals ae clocked by the TX clock. The sigal ames ae stadad TX MAC Avalo Steamig Cliet Iteface sigals with slight diffeeces to idicate the vaiatios.
Sigal Name Width Desciptio
Iput Sigals
i_tx_data[63:0] 64 bits

Iput data (Etheet Fame. Requied cotet depeds o the featues eabled duig IP cofiguatio) to the MAC whe the ate is 10GE/25GE. Bit 0 is the Least Sigificat Byte (LSB).

i_tx_valid 1 bit

Dive this sigal high (HI) to qualify all iput sigals ad buses i this table. This sigal must be cotiuously asseted betwee the assetios of the stat of packet ad ed of packet sigals fo the same packet.

i_tx_statofpacket 1 bit

Stat of Packet (SOP)

Whe asseted, idicates that the TX data holds the fist clock cycle of data i a packet (stat of packet). Asset fo oly a sigle clock cycle fo each packet. Whe the SOP sigal is asseted, the MSB of the TX data dives the stat of packet.

i_tx_edofpacket 1 bit

Ed of Packet (EOP)

Whe asseted, idicates that the TX data holds the fial clock cycle of data i a packet (ed of packet). Asset fo oly a sigle clock cycle fo each packet.

Fo some legitimate packets, the SOP ad EOP sigals ae asseted o the same clock cycle.

i_tx_empty[2:0] 3 bits

Idicates the umbe of empty bytes o the TX data whe the EOP sigal is asseted.

i_tx_eo 1 bit

Whe asseted i a EOP cycle (while the EOP sigal is asseted), diects the IP coe to iset a eo i the packet befoe sedig it o the Etheet lik.

i_tx_skip_cc 1 bit

Dive this sigal high fo the duatio of the fame tasfe to disable CRC bytes ad souce addess isetio by the IP coe fo the cuet fame. This meas you povide the souce addess ad CRC bytes.

If this sigal is asseted, diects the TX MAC to ot iset CRC, ot add paddig bytes, ad ot implemet souce addess isetio.

If this sigal is ot asseted, ad souce addess isetio is eabled, the TX MAC pefoms the followig:
  • Ovewites the souce addess field with the value pogammed i the TXMAC_SADDR egiste.
  • If ecessay, the TX MAC isets paddig bytes ad a CRC i the packet.
Output Sigals
o_tx_eady 1 bit

Idicates that the IP is eady to accept data. If o_tx_eady is emoved, the the i_tx_valid must also be emoved afte the cofigued eady latecy settigs i the IP GUI.