UM10503
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2012. All rights reserved.
User manual
Rev. 1.3 — 6 July 2012
717 of 1269
NXP Semiconductors
UM10503
Chapter 26: LPC43xx Ethernet
26.6.37 DMA Current host transmit descriptor register
The Current Host Transmit Descriptor register points to the start address of the current
Transmit Descriptor read by the DMA.
26.6.38 DMA Current host receive descriptor register
The Current Host Receive Descriptor register points to the start address of the current
Receive Descriptor read by the DMA.
26.6.39 DMA Current host transmit buffer address register
The Current Host Transmit Buffer Address register points to the current Transmit Buffer
Address being read by the DMA.
Table 570. DMA Receive interrupt watchdog timer register (DMA_REC_INT_WDT, address
0x4001 1024) bit description
Bit
Symbol
Description
Reset
value
Access
7:0
RIWT
RI watchdog timeout
Indicates the number of system clock cycles multiplied by
256 for which the watchdog timer is set. The watchdog timer
gets triggered with the programmed value after the RxDMA
completes the transfer of a frame for which the RI status bit
is not set due to the setting in the corresponding descriptor
RDES1[31]. When the watch-dog timer runs out, the RI bit is
set and the timer is stopped. The watchdog timer is reset
when RI bit is set high due to automatic setting of RI as per
RDES1[31] of any received frame.
0
R/W
31:8
-
Reserved
0
RO
Table 571. DMA Current host transmit descriptor register (DMA_CURHOST_TRANS_DES,
address 0x4001 1048) bit description
Bit
Symbol
Description
Reset
value
Access
31:0
HTD
Host Transmit Descriptor Address Pointer
Cleared on Reset. Pointer updated by DMA during
operation.
0
RO
Table 572. DMA Current host receive descriptor register (DMA_CURHOST_REC_DES,
address 0x4001 104C) bit description
Bit
Symbol
Description
Reset
value
Access
31:0
HRD
Host Receive Descriptor Address Pointer
Cleared on Reset. Pointer updated by DMA during
operation.
0
RO