Low Latency 40G for ASIC Proto Ethernet Intel® FPGA IP User Guide

ID 683221
Date 11/10/2022
Public
Document Table of Contents

7.3. RX MAC Registers

Table 28.  RX MAC Registers
Addr Name Description Reset Access
0x500 RXMAC_REVID

RX MAC revision ID for Low Latency 40G for ASIC Proto Ethernet IP core.

0x0627 2016 RO
0x501 RXMAC_SCRATCH Scratch register available for testing. 0x0000 0000 RW
0x502 RXMAC_NAME_0

First 4 characters of IP core variation identifier string, "40gMACRxCSR".

0x3430 674D

RO

0x503 RXMAC_NAME_1 Next 4 characters of IP core variation identifier string, "ACRx". 0x4143 5278

RO

0x504 RXMAC_NAME_2 Final 4 characters of IP core variation identifier string, "0CSR". The "0" is unprintable. 0x0043 5352

RO

0x506 MAX_RX_SIZE_CONFIG Specifies the maximum frame length available. The MAC asserts when the length of the received frame exceeds the value of this register.

If the IP core receives an Ethernet frame of size greater than the number of bytes specified in this register, and the IP core includes statistics registers, the IP core increments the 64-bit CNTR_RX_OVERSIZE counter.

0xXXXX 2580 4

RW

0x507 MAC_CRC_CONFIG The RX CRC forwarding configuration register. The following encodings are defined:
  • 1'b0: Remove RX CRC, do not forward it to the RX client interface
  • 1'b1: Retain RX CRC, forward it to the RX client interface
In either case, the IP core checks the incoming RX CRC and flags errors.
31'hX1'b0 4

RW

0x508 LINK_FAULT

Link Fault Status Register.

  • Bit[0]: Local fault status bit.
  • Bit[1]: Remote fault status bit.

For regular (non-unidirectional) Link Fault, implements IEEE 802.3 BA Ethernet Clause 81.3.4.

For unidirectional Link Fault, implements IEEE 802.3 Ethernet Clause 66.

30'hX2'b00 4

RO

0x50A RX_MAC_CONTROL RX MAC Control Register. The following bits are defined:
  • Bit[4]: Preamble check. Strict SFD checking option to compare each packet preamble to 0x555555555555. This field is available only if you turn on Enable Strict SFD check .
  • Bit[3]: SFD check. Strict SFD checking option to compare each SFD byte to 0x5D. This field is available only if you turn on Enable Strict SFD check .
  • Bit [1]: VLAN detection disabled. This bit is deasserted by default implying VLAN detection is enabled.
30'h0_2'b0X 4 RW
4 X means "Don't Care".