LG MG810c Service Manual page 25

3. H/W Circuit Description
F. USB Interface
The USB_W2FC module supports the implementation of a "Full-Speed" device fully compliant to USB
1.1 standard. It provides an interface between the MCU and the USB device and handles USB
transactions with minimal MCU intervention.
The USB_W2FC module supports one control endpoint (EP0), up-to fifteen (15) IN endpoints and up-
to fifteen (15) OUT endpoints. The exact endpoint configuration is software programmable. The
specific items configurable for each endpoint are the size in bytes, the direction (IN, OUT), the type
(Bulk/Interrupt or ISO), and the associated endpoint number.
The USB_W2FC module also supports three DMA channels for IN endpoints and three DMA channels
for OUT endpoints for either Bulk/Interrupt or ISO transactions. In operation, the USB requires a
48MHz clock generated by a dedicated embedded DPLL upon request. The USB module interface is
PVCI compliant. Therefore this module interfaces with the TI MCU RHEA bus via a RHEA-PVCI
bridge.
Calypso-Plus integrates differential drivers to allow a glue-less connection with any host. The required
3.3V VDD is provided by the VBUS signal taken from the USB connector.
- USB_DP : USB differential (+) line.
- USB_DM : USB differential (-) line.
- USB_PU_EN : USB pull-up enable.
- MAP_USB_P : MAP(Corelogic) USB differential(+) line
- MAP_USB_N : MAP(Corelogic) USB differential(-) line
- USB_PATH_SEL : choice either DBB or MAP(Corelogic)
Figure 9. USB interface diagram
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