CHAPTER 6 USB CONTROLLER
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Preliminary User’s Manual S15543EJ1V0UM
6.6.6 USB controller receive processing
This section presents all of the processing performed by USB Controller at data receiving.
6.6.6.1 Normal mode
The following figure illustrates the receive operations performed by USB Controller in Normal Mode.
Figure 6-21. USB Controller Receive Operations (Normal Mode)
Stores the data from USB to
receive FIFO
Receives data
from USB
- CRC verify
- Bit Stuffing verify
- NRZI decode
Encounters link pointer ?
Yes
No
DMA transfers to
system memory
Writes Rx indication
Updates write pointer,
Sets Rx completion bit of corresponding
EndPoint in U_GSR register
(1)
(2)
(5)
(7)
(8)
(9)
(3)
Waits data
Fetches a new
buffer directory
Updates pool
Information Registers
(4)
(6)