VLAN TPID Word 1 Register - 7.2 English

AXI 1G/2.5G Ethernet Subsystem Product Guide (PG138)

Document ID
PG138
Release Date
2023-11-15
Version
7.2 English

The VLAN TPID Word 1 (TPID1) register is shown in the following figure. This register is only used when transmit and/or receive VLAN functions are included in the subsystem at build-time (C_TXVLAN_TAG = 1 and/or C_RXVLAN_TAG = 1 and/or C_TXVLAN_STRP= 1 and/or C_RXVLAN_STRP= 1 and/or C_TXVLAN_TRAN = 1 and/or C_RXVLAN_TRAN = 1). This register and the previous register allow four TPID values to be specified for recognizing VLAN frames for both the transmit and receive paths. The most common values for VLAN TPID are 0x8100, 0x9100, 0x9200, 0x88A8. See Extended VLAN Support for more information.

Figure 1. VLAN TPID Word 1 Register (0x0000_002C) AXI Ethernet Page-1 Sheet.1 Sheet.2 TPID value 4 TPID value 4 Sheet.3 TPID value 3 TPID value 3 Sheet.4 MSB MSB Sheet.5 LSB LSB Sheet.6 Sheet.7 15 15 Sheet.8 0 0 Sheet.9 16 16 Sheet.10 31 31 Sheet.11 X14037 X14037

The following table shows the VLAN TPID Word 1 register bit definitions.

Table 1. VLAN TPID Word 1 Register (0x0000_002C)
Bits Name Access Reset Value Description
31:16 TPID value 3 R/W 0x0 TPID Value 3: These bits represent one TPID value that is used to recognize VLAN frames for both the transmit and receive paths.
15:0 TPID value 2 R/W 0x0 TPID Value 2: These bits represent one TPID value that is used to recognize VLAN frames for both the transmit and receive paths.