Datasheet

636
32072H–AVR32–10/2012
AT32UC3A3
FIFO size (i.e. the DPRAM size), so the value of CFGOK does not consider memory
allocation conflicts.
27.7.1.7 Pad Suspend
Figure 27-8 on page 636 shows the pad behavior.
Figure 27-8. Pad Behavior
• In the Idle state, the pad is put in low power consumption mode, i.e., the differential receiver
of the USB pad is off, and internal pull-down with strong value(15K) are set in both DP/DM to
avoid floating lines.
• In the Active state, the pad is working.
Figure 27-9 on page 636 illustrates the pad events leading to a PAD state change.
Figure 27-9. Pad Events
The SUSP bit is set and the Wake-Up Interrupt (WAKEUP) bit in UDINT is cleared when a USB
“Suspend” state has been detected on the USB bus. This event automatically puts the USB pad
in the Idle state. The detection of a non-idle event sets WAKEUP, clears SUSP and wakes up
the USB pad.
Idle
Active
USBE = 1
& DETACH = 0
& Suspend
USBE = 0
| DETACH = 1
| Suspend
SUSP
Suspend detected Cleared on wake-up
Wake-up detected Cleared by software to acknowledge the interrupt
WAKEUP
PAD State
Active
Idle
Active