DF2211NP24V Renesas Technology / Hitachi Semiconductor, DF2211NP24V Datasheet - Page 555

• Manufacturer Part Number: DF2211NP24V
• Description: H8S/2200 Series, 2212 Group, USB, RTC, HSS TNP-64B; Vcc= 2.7 to 3.6 volts, Temp= -20 to 75 C; Package: PVQN0064LB-A
• Manufacturer: Renesas Technology / Hitachi Semiconductor

(4) USB Cable Disconnection (When USB module stop or power-down mode is used)
If the USB cable enters the disconnection state from the connection state in an application (self
powered) where USB module stop or power-down mode is used, perform the operation as
shown in figure 14.6.
Notes:
Disconnect the USB cable
stabilization detection
clock stabilization time
USB operating clock
Start USB operating
1.
2.
interrupt occurs.
clock oscillation
Reset UDC core
USB operating
has passed?
VBUS interrupts in the USB module cannot be detected in power-down mode or in the USB
module stop state. Accordingly, in an application (self powered) where power-down mode or
USB module stop is used , VBUS interrupts of the USB must bedetected via the external
interrupt pin IRQx. In this case, the IRQx pin must be specified as both edge sensitive.
When IRQx is used, VBUS interrupts in the USB module need not to be used.
Before entering power-down mode, make sure to set USB module stop2 (the MSTPB0 bit of
MSTPCRB = 1).
USB function
Yes
(When USB Module Stop or Power-Down Mode Is Used)
Figure 14.6 USB Cable Disconnection
No
*
1
External interrupt IRQx*
EXIRQx
Yes
Clear MSTPB0 in MSTPCRB to 0
Clear CK48READY in UIFR3 to 0
Write MSTPB0 in MSTPCRB to 1
Wait for USB operating clock
Write UDCRST in UCTRL to 1
Check connections by using
Cancel USB module stop 2
Enter power-down mode
the port function of IRQx
Powe-down mode ?
(only if necessary)
enter power-down
cable connection
Enable D+ pull-up
Stop USB module
System needs to
Reset UDC core
by port 36 (P36)
USB module
stabilization
Wait for USB
Yes
Rev.7.00 Dec. 24, 2008 Page 501 of 698
1
Firmware
stopped?
mode?
Yes
No
No
*
*
No
2
2
Check the USB cable
disconnection state
REJ09B0074-0700