EFM32WG Datasheet, PDF (331/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

...the world's most energy friendly microcontrollers
• Slave mode
Minimum requirement: (largest USB packet used / 4) + 1 for status information + 1 transfer complete
• DMA mode
(largest USB packet used / 4) + 1 for status information + 1 transfer complete + 1 location each bulk/
control out endpoint for handling NAK scenario
Host Non-Periodic TxFIFO =
• largest non-periodic USB packet used / 4
Host Periodic TxFIFO =
• Sum total of (MPS*MC)/4 of all periodic channels or 1500 locations, whichever is lower.
Device IN Endpoint TxFIFOs (a separate FIFO is allocated to each IN endpoint) =
• IN Endpoints Max packet Size / 4
Method 2
Use this method if you are using the recommended minimum FIFO depth allocation with support for
high-bandwidth endpoints. This FIFO allocation enables the core to transfer a packet on the USB while
the previous (next) packet is simultaneously transferred to the AHB. This FIFO allocation improves the
core’s performance.
Device RxFIFO =
• (4 * number of control endpoints + 6) + 2 * ((largest USB packet used / 4) + 1) +(2 * number of OUT
endpoints) + 1
Host RxFIFO =
• Slave mode
2 * ((largest USB packet used / 4) + 1 + 1)
• DMA mode
2 * ((largest USB packet used / 4) + 1 + 1) + 1 location each bulk/control out endpoint for handling
NAK scenario
Host Non-Periodic TxFIFO =
• 2 * (largest non-periodic USB packet used / 4)
Host Periodic TxFIFO =
• Sum total of (MPS*MC)/4 for all periodic channels or 1500 location, whichever is lower.
Device IN Endpoint-Specific TxFIFOs (a separate FIFO is allocated to each endpoint) =
• 2 * (max_pkt_size for the endpoint) / 4.
//DMA mode
OTG Total RAM = (Device RxFIFO or Host RxFIFO; choose the largest one) +
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
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