Sundance Technology
ST201
PRELIMINARY draft 2
TXRELEASETHRESH
Class | I/O Registers, FIFO Control |
Base Address | IoBaseAddress register value |
Address Offset | 0x5d |
Access Mode | Read/Write |
Width | 8 bits |
The value in TxReleaseThresh determines how much data of a frame must be transmitted before the TxFIFO space can be released for use by another frame. Once the number of bytes equal to the value in TxReleaseThresh have been transmitted, that number of bytes are discarded from the TxFIFO. Thereafter, bytes are discarded as they are transmitted to the network. TxReleaseThresh resets to 8, i.e., a release threshold of 128 bytes. A value of 255 in TxReleaseThresh disables the release mechanism and TxFIFO frame space is not released until the entire frame is transmitted. A TxReleaseError is signaled in TxStatus when a frame experiences a collision after its release threshold has been crossed, preventing MAC from retry. When a release error occurs, the transmitter is disabled, and the frame’s ID or sequence number is visible in TxFrameId.
BIT
7..0
BIT NAME
TxReleaseThresh
BIT DESCRIPTION
The number of 16 byte words which must be transmitted before the space in the TxFIFO occupied by the transmitted data can be released. To avoid excessive release errors due to
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