Datasheet

Section 22 USB Function Module (USB)
Rev. 2.00 Aug. 20, 2008 Page 869 of 1198
REJ09B0403-0200
(4) Remote-Wakeup Operation
When the USB bus enters the non-suspend (resume) state from the suspend state by the remote-
wakeup signal output from this function, processing should proceed as shown below.
USB cable connected
USB bus in suspend state
Cancel software
standby mode
Clear SURSF in IFR2 to 0
Check if SURSS in IFR2 is
cleared to 0
Software standby
mode ?
USB module
stopped?
Oscillation
stabilization time
has passed?
No
No
No
Ye s
Ye s
Ye s
Start USB operating
clock oscillation
Cancel USB module stop
Remote wakeup execution
(CTLR/RSME= 1)
Return to normal state
Ye s
No
Bus wakeup source
generated
Remote
wakeup enabled?
(CTLR/RWUPS = 1?)
Wait for resume
from up-stream
Resume output signal
Suspend/resume
interrupt occurs.
(IFR2/SURSF = 1)
RESUME
USB function
Application
Figure 22.8 Remote-Wakeup