Renesas H8S/2158 User Manual page 632

Section 18 Universal Serial Bus Interface (USB)
Bit Bit Name Initial Value R/W
4 EP3TF 0
3 EP2TF 0
Rev. 3.00 Jan 25, 2006 page 578 of 872
REJ09B0286-0300
Description
R/(W) * Endpoint 3 Transfer Failure Flag
Indicates that the endpoint 3 host input transfer has been
completed abnormally.
0: Indicates that the endpoint 3 is in a transfer wait state.
[Clearing condition]
•
0 is written to EP3TF after EP3TF = 1 has been read.
1: Indicates that the endpoint 3 host input transfer (IN
transaction) has been completed abnormally.
[Setting conditions]
•
An ACK handshake cannot be achieved after IN
token has been received and data has been
transferred.
•
Data cannot be sent because the FIFO is empty after
an IN token has been received (NAK transmission).
R/(W) * Endpoint 2 Transfer Failure Flag
Indicates that the endpoint 2 host input or output transfer
has been completed abnormally.
0: Indicates that the endpoint 2 is in a transfer wait state.
[Clearing condition]
•
0 is written to EP2TF after EP2TF = 1 has been read.
1: Indicates that the endpoint 2 host input transfer (IN
transaction) or output transfer (OUT transaction) has
been completed abnormally.
[Setting conditions]
•
An ACK handshake cannot be achieved after IN
token has been received and data has been
transferred.
•
Data cannot be sent because the FIFO is empty after
an IN token has been received (NAK transmission).
•
Data cannot be received because the FIFO is full
after an OUT token has been received (NAK
transmission).
•
A communication error occurs after the OUT token
has been received.