CHAPTER 12 USB FUNCTION CONTROLLER (USBF)
Preliminary User’s Manual U19014EJ1V0UD
327
Figure 12-4. Operation of UF0E0W Register
(a) 16-byte transmission
Status of
UF0E0W register
Trans-
mission
starts
Trans-
mission
completed
ACK
reception
Trans-
mission
starts
Trans-
mission
completed
Re-
trans-
mission
starts
ACK
reception
ACK
cannot be
received
EP0NKW bit of
UF0E0N register
EP0W
bit of
UF0EPS0
register
E0INDT
bit of
UF0IS1
register
FIFO full
Hardware clear
FIFO full
16-byte transfer
16-byte transfer
Re-transfer
INT clear
(FW clear)
Writing
FIFO
starts
Writing
FIFO
completed
Writing
FIFO
starts
Writing
FIFO
completed
Counter
reloaded
Hardware
clear
Hardware
clear
(b) When Null packet or short packet is transmitted
Status of
UF0E0W register
Transmission
starts
Trans-
mission
completed
ACK
reception
Transmission
starts
Trans-
mission
completed
ACK
reception
EP0NKW bit of
UF0E0N register
EP0W
bit of
UF0EPS0
register
E0INDT
bit of
UF0IS1
register
Hardware clear
E0DED bit of
UF0DEND
register is set.
E0DED bit of
UF0DEND
register is set.
Short packet transfer
Transfer of Null packet
INT clear
(FW clear)
Writing
FIFO
starts
Writing
FIFO
completed
FIFO FW
clear
electronic components distributor