EMAC Module Registers
1916
SPNU563A – March 2018
Copyright © 2018, Texas Instruments Incorporated
EMAC/MDIO Module
32.5.46 Transmit Channel DMA Head Descriptor Pointer Registers (TX0HDP-TX7HDP)
The transmit channel 0-7 DMA head descriptor pointer register (TX
n
HDP) is shown in
and
described in
Figure 32-87. Transmit Channel n DMA Head Descriptor Pointer Register (TXnHDP)
(offset = 600h-61Ch)
31
0
TX
n
HDP
R/W-x
LEGEND: R/W = Read/Write; -
n
= value after reset; -x = value is indeterminate after reset
Table 32-85. Transmit Channel n DMA Head Descriptor Pointer Register (TXnHDP)
Field Descriptions
Bit
Field
Description
31-0
TX
n
HDP
Transmit channel
n
DMA Head Descriptor pointer. Writing a transmit DMA buffer descriptor address to a head
pointer location initiates transmit DMA operations in the queue for the selected channel. Writing to these
locations when they are nonzero is an error (except at reset). Host software must initialize these locations to 0
on reset.
32.5.47 Receive Channel DMA Head Descriptor Pointer Registers (RX0HDP-RX7HDP)
The receive channel 0-7 DMA head descriptor pointer register (RX
n
HDP) is shown in
and
described in
Figure 32-88. Receive Channel n DMA Head Descriptor Pointer Register (RXnHDP)
(offset = 620h-63Ch)
31
0
RX
n
HDP
R/W-x
LEGEND: R/W = Read/Write; -
n
= value after reset; -x = value is indeterminate after reset
Table 32-86. Receive Channel n DMA Head Descriptor Pointer Register (RXnHDP)
Field Descriptions
Bit
Field
Description
31-0
RX
n
HDP
Receive channel
n
DMA Head Descriptor pointer. Writing a receive DMA buffer descriptor address to this
location allows receive DMA operations in the selected channel when a channel frame is received. Writing to
these locations when they are nonzero is an error (except at reset). Host software must initialize these
locations to 0 on reset.