36.14.1 TX Control Status Register Low for Endpoint 1-7

Table 36-91. Register Bit Attribute Legend
Symbol Description Symbol Description Symbol Description
R Readable bit HC Cleared by Hardware (Grey cell) Unimplemented
W Writable bit HS Set by Hardware X Bit is unknown at Reset
K Write to clear S Software settable bit
Name: TXCSRL
Offset: 0x1012
Reset: 0x0000
Property: PAC Write-Protection

Bit 76543210 
 INCOMPRXCLRDTSENTSTALLSENDSTALLFLUSHFIFOUNDERRUNFIFONETXPKTRDY 
Access R/W/HSR/WR/WR/WR/W/HCR/WR/WR/W 
Reset 00000000 

Bit 7 – INCOMPRX Incomplete Packet Status bit

In anything other than Isochronous transfer, this bit will always return 0.

ValueDescription
0 Written by the software to clear this bit
1 The packet in the RX FIFO during a high-bandwidth Isochronous/Interrupt transfer is incomplete because parts of the data were not received

Bit 6 – CLRDT Clear Data Toggle Control Bit

ValueDescription
0 Do not clear the data toggle
1 Resets the endpoint data toggle to 0

Bit 5 – SENTSTALL Stall Handshake Status Bit

ValueDescription
0 Written by the software to clear this bit
1 STALL handshake is transmitted

Bit 4 – SENDSTALL STALL Handshake Control bit

ValueDescription
0 Terminate stall condition
1 Issue a STALL handshake

Bit 3 – FLUSHFIFO FIFO Flush Control bit

ValueDescription
0 Do not flush the FIFO
1 Flush the latest packet from the endpoint TX FIFO. The FIFO pointer is reset, the TXPKTRDY bit is cleared and an interrupt is generated.

Bit 2 – UNDERRUN Underrun Status bit

ValueDescription
0 Written by software to clear this bit.
1 An IN token has been received when the TXPKTRDY bit is not set.

Bit 1 – FIFONE FIFO Not Empty Status bit

ValueDescription
0 TX FIFO is empty
1 There is at least 1 packet in the TX FIFO

Bit 0 – TXPKTRDY TX Packet Ready Control bit

The software sets this bit after loading a data packet into the FIFO. It is cleared automatically when a data packet has been transmitted. This bit is also automatically cleared prior to loading a second packet into a double-buffered FIFO.