10.3.5.9.5 STALL

STALL is returned by a function in response to an IN token or after the data phase of an OUT or in response to a PING transaction. STALL indicates that a function is unable to transmit or receive data, or that a control pipe request is not supported.

  • OUT

To stall an endpoint, set the FRCESTALL bit in UDPHS_EPTSETSTAx register and after the STALL_SNT flag has been set, set the TOGGLE_SEG bit in the UDPHS_EPTCLRSTAx register.

  • IN

Set the FRCESTALL bit in UDPHS_EPTSETSTAx register.

Figure 10-22. Stall Handshake Data OUT Transfer

Figure 10-23. Stall Handshake Data IN Transfer