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“14. Oscillators” on page 135 for more details on internal oscillator configuration, including the Suspend mode feature of the internal oscillator.
USB0 exits Suspend mode when any of the following occur: (1) Resume signaling is detected or gener- ated, (2) Reset signaling is detected, or (3) a device or USB reset occurs. If suspended, the internal oscil- lator will exit Suspend mode upon any of the above listed events.
Resume Signaling: USB0 will exit Suspend mode if Resume signaling is detected on the bus. A Resume interrupt will be generated upon detection if enabled (RESINTE = ‘1’). Software may force a Remote Wakeup by writing ‘1’ to the RESUME bit (POWER.2). When forcing a Remote Wakeup, software should write RESUME = ‘0’ to end Resume signaling
ISO Update: When software writes ‘1’ to the ISOUP bit (POWER.7), the ISO Update function is enabled. With ISO Update enabled, new packets written to an ISO IN endpoint will not be transmitted until a new
USB Enable: USB0 is disabled following a
USBINH bit (POWER.4). Once written to ‘0’, the USBINH can only be set to ‘1’ by one of the following: (1) a
Software should perform all USB0 configuration before enabling USB0. The configuration sequence should be performed as follows:
Step 1. Select and enable the USB clock source.
Step 2. Reset USB0 by writing USBRST= ‘1’.
Step 3. Configure and enable the USB Transceiver.
Step 4. Perform any USB0 function configuration (interrupts, Suspend detect).
Step 5. Enable USB0 by writing USBINH = ‘0’.
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