EFM32WG Datasheet, PDF (262/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

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2. The Device responds with NAK.
3. If the application has unmasked NAK, the core generates the corresponding interrupt(s) to the
application.
The application is not required to service these interrupts, since the core takes care of rewinding of
buffer pointers and re-initializing the Channel without application intervention.
4. When the Device returns an ACK, the core continues with the transfer.
Optionally, the application can utilize these interrupts. If utilized by the application:
• The NAK interrupt is masked by the application.
• The core does not generate a separate interrupt when NAK is received by the Host functionality.
Application Programming Flow
1. The application programs a channel to do a bulk transfer for a particular data size in each transaction.
• Packet Data size can be up to 512 KBytes
• Zero-length data must be programmed as a separate transaction.
2. Program the transfer size register with:
• Transfer size
• Packet Count
3. Program the DMA address.
4. Program the USB_HCx_CHAR to enable the channel.
5. The Interrupt handling by the application is as depicted in the flow diagram.
Note
The NAK interrupts are still generated internally. The application can mask off these
interrupts from reaching it. The application can use these interrupts optionally.
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
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