EFM32WG Datasheet, PDF (332/834 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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((Host Non-Periodic TxFIFO + Host peiodic TxFIFO) or
(Device IN Endpoint TxFIFO #0 + #1 + #2 + #n)); choose the largest one +
(1 location per Host channel or 1 location per Device Endpoint direction; choose
the largest one)
//Slave mode
OTG Total RAM = (Device RxFIFO or Host RxFIFO; choose the largest one) +
((Host Non-Periodic TxFIFO + Host peiodic TxFIFO) or
(Device IN Endpoint TxFIFO #0 + #1 + #2 + #n)); choose the largest one
Method 3
Use this method if you are using the recommended FIFO depth allocation that supports high-bandwidth
endpoints and high AHB latency.
Note
• x = (AHB latency + time to transfer largest packet on AHB) / time to transfer largest
packet on USB.
• The value of x is an integer. Any fractional value is rounded to the nearest integer. For
example: x = 20 ms / 17,039 ms = 1.17 ms = 2 ms.
Device RxFIFO =
• (4 * number of control endpoints + 6) + (x + 1) * ((largest USB packet used / 4) + 1)+ (2 * number
of OUT endpoints) + 1
Note
Include the Control OUT endpoint in the number of OUT endpoints.
Host RxFIFO =
• Slave mode
(x + 1) * ((largest USB packet used / 4) + 1 + 1)
• DMA mode
(x + 1) * ((largest USB packet used / 4) + 1 + 1) + 1 location each bulk/control out endpoint for handling
NAK scenario
Host Non-Periodic TxFIFO =
• (x + 1) * (largest non-periodic USB packet used / 4)
Host Periodic TxFIFO =
• (x+1) * (Sum total of (MPS*MC)/4 of all periodic channels or 1500 locations, whichever is lower).
Device IN Endpoint-Specific TxFIFOs (a separate FIFO is allocated to each endpoint) =
• (x+1)*(max_pkt_size for the endpoint)/4
//DMA mode
OTG Total RAM = (Device RxFIFO or Host RxFIFO; choose the largest one) +
((Host Non-Periodic TxFIFO + Host periodic TxFIFO) OR
(Device IN Endpoint TxFIFO #0 + #1 + #2 + #n); choose the largest one) +
(1 location per Host channel or 1 location per Device Endpoint direction; choose
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
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