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Section 20 USB Function Module
Rev. 4.00 Sep. 14, 2005 Page 792 of 982
REJ09B0023-0400
Normal routine
IRQ1 interrupt routine
Normal state
Clear IRR0/IRQ1R of INTC
Save SSR and SPC
to memory
Set STBCR/STBY
SLEEP instruction
Set SR/I[3:0] to the IRQ1
priority
Clear IRR0/IRQ0R of INTC
RTE instruction
Clear USBIFR2/SUSPS and
AWAKE (clear detection of USB
suspend and AWAKE signals)
IRQ1 interrupt?
IRR0/IRQ0R of INTC?
No
1
0
Yes
Normal operation
Standby mode
Figure 20.22 Sample Flowchart for Changing the State from USB Suspend to Standby