CHAPTER 12 USB FUNCTION CONTROLLER (USBF)
Preliminary User’s Manual U19014EJ1V0UD
351
12.5 STALL Handshake or No Handshake
Errors of USBF are defined to be handled as follows.
Transfer Type
Transaction
Target
Packet
Error Type
Function
Response
Processing
Endpoint not supported
No response
None
Endpoint transfer
direction mismatch
No response
None
CRC error
No response
None
IN/OUT/SETUP Token
Bit stuffing error
No response
None
Timeout No
response
None
PID check error
No response
None
Unsupported PID
(other than Data PID)
No response
None
CRC error
No response
Discard received data
OUT/SETUP Data
Bit stuffing error
No response
Discard received data
Control transfer/
bulk transfer
OUT
Data
Data PID mismatch
ACK
Discard received data
Control transfer
(SETUP stage)
SETUP
Data
Overrun
No response
Discard received data
Control transfer
(data stage)
OUT Data
Overrun
No
response
Note 1
Set SNDSTL bit of
UF0SDS register to 1 and
discard received data
Control transfer
(status stage)
OUT
Data
Overrun
ACK or
no response
Note 2
Set SNDSTL bit of
UF0SDS register to 1 and
discard received data
Bulk transfer
OUT
Data
Overrun
No response
Note 1
Set EnHALT bit of
UF0EnSL register (n = 0 to
2) to 1
PID check error
−
Hold transferred data and
re-transfer data
Note 3
Unsupported PID
(other than ACK PID)
−
Hold transferred data and
re-transfer data
Note 3
Control transfer/
bulk transfer
IN Handshake
Timeout
−
Hold transferred data and
re-transfer data
Note 3
Notes 1.
A STALL response is made to re-transfer by the host.
2.
An ACK response is made if the transfer data is of less than MaxPacketSize and the data received in the
status stage is discarded. If MaxPacketSize is exceeded, no response is made, the SNDSTL bit of the
UF0SDS register is set to 1, and the received data is discarded.
3.
If an OUT transaction indicating a change from the data stage to the status stage is received during
control transfer, an error is not handled and it is assumed that reception has been correctly completed.
Cautions 1. It is judged by the Alternative Setting number currently set whether the target endpoint is
valid or invalid.
2. For the response to the request included in control transfer to/from Endpoint0, see 12.3
Requests.
electronic components distributor