Sundance Technology
ST201
PRELIMINARY draft 2
TXDMAURGENTTHRESH
Class | I/O Registers, DMA |
Base Address | IoBaseAddress register value |
Address Offset | 0x09 |
Access Mode | Read/Write |
Width | 8 bits |
When the number of used bytes in the TxFIFO falls below the value in the TxDMAUrgentThresh, the TxDMA Logic will make an urgent bus master request. An urgent TxDMA request will have priority over the RxDMA, unless it is also making an urgent request. A TxDMA urgent request is not subject to the TxDMABurstThresh constraint. The relaxation of the TxDMABurstThresh constraint for this condition is because the TxFIFO is close to under run, and burst efficiency is sacrificed to avoid FIFO under run. The value in TxDMAUrgentThresh represents data in the TxFIFO in multiples of 32 bytes. TxDMAUrgent- Thresh resets to 4, or a threshold of 128 bytes.
BIT
5..0
7..6
BIT NAME
TxDMAUrgent- Thresh
Unused
BIT DESCRIPTION
The minimum number of
These bits are ignored.
81
