dmagrp_transmit_poll_demand

          Register 1 (Transmit Poll Demand Register) 

The Transmit Poll Demand register enables the Tx DMA to check whether or not the DMA owns the current descriptor. The Transmit Poll Demand command is given to wake up the Tx DMA if it is in the Suspend mode. The Tx DMA can go into the Suspend mode because of an Underflow error in a transmitted frame or the unavailability of descriptors owned by it. You can give this command anytime and the Tx DMA resets this command when it again starts fetching the current descriptor from host memory. When this register is read, it always returns zero.
      
Module Instance Base Address Register Address
i_emac_emac0 0xFF800000 0xFF801004
i_emac_emac1 0xFF802000 0xFF803004
i_emac_emac2 0xFF804000 0xFF805004

Size: 32

Offset: 0x1004

Access: RW

Important: The value of a reserved bit must be maintained in software. When you modify registers containing reserved bit fields, you must use a read-modify-write operation to preserve state and prevent indeterminate system behavior.
Bit Fields
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16

tpd

RW 0x0

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

tpd

RW 0x0

dmagrp_transmit_poll_demand Fields

Bit Name Description Access Reset
31:0 tpd
Transmit Poll Demand

When these bits are written with any value, the DMA reads the current descriptor pointed to by Register 18 (Current Host Transmit Descriptor Register). If that descriptor is not available (owned by the Host), the transmission returns to the Suspend state and the Bit 2 (TU) of Register 5 (Status Register) is asserted. If the descriptor is available, the transmission resumes.
RW 0x0