Transmit VLAN Tag 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 Transmit VLAN Tag (TTAG) register is shown in the following figure. This register is only used when the VLAN tagging is included in the subsystem at build-time (C_TXVLAN_TAG = 1). When a VLAN tag is added to a transmit frame, this is the value that is added to the frame right after the source address field. See Extended VLAN Support for more information about how VLAN tagging is performed.

Figure 1. Transmit VLAN Tag Register (0x0000_0018) AXI Ethernet Page-1 Sheet.3 X14032 X14032 Sheet.4 MSB MSB Sheet.5 LSB LSB Sheet.6 Sheet.11 Sheet.12 Sheet.13 Sheet.14 VID VID Sheet.17 Priority Priority Sheet.18 CFI CFI Sheet.21 TPID TPID Sheet.22 11 11 Sheet.23 12 12 Sheet.24 16 16 Sheet.25 13 13 Sheet.26 15 15 Sheet.27 0 0 Sheet.28 31 31 Standard Arrow.59 Standard Arrow.2 Standard Arrow.7 Standard Arrow.8

The following table shows the Transmit VLAN Tag register bit definitions.

Table 1. Transmit VLAN Tag Register (0x0000_0018)
Bits Name Access Reset Value Description
31:16 TPID R/W 0x0 Tag Protocol Identifier.
15:13 Priority R/W 0x0 User Priority.
12 CFI R/W 0 Canonical Format Indicator.
11:0 VID R/W 0x0 VLAN identifier:Uniquely identifies the VLAN to which the frame belongs.