CHAPTER 12 USB FUNCTION CONTROLLER (USBF)
Preliminary User’s Manual U19014EJ1V0UD
388
12.7.5 Processing after power application
The processing to be performed after power application differs depending on the configuration of the system. One
example is given below.
Figure 12-25. Example of Processing After Power Application/Power Failure (1/3)
(a) Processing after power application (1/2)
Yes
Resume
detected?
No
START
START
Controlling port
Note 2
Pull-up processing of
D+ inactive
Note 1
Pull-up processing
of D+ active
Note 1
Connection
Controlling port
Note 2
BUSRST = 1 (UF0IS0)
DFLT = 1 (UF0MODS)
Initialization of request
data register
Initialization of request
data register
:
See
Figure 12-10 Initialization
of Request Data Register
.
:
See
Figure 12-10 Initialization
of Request Data Register
.
(a)
Notes 1.
Use one general-purpose port pin for the signal that controls switching of the pull-up resistor of the
USB bus.
2.
The input mode or control mode of the general-purpose port pin allocated in
Note 1
may be selected
as the default value. Note the active level of pull-up processing of D+ on power application.
Remark
♦
: Processing by hardware
electronic components distributor