Texas Instruments Tiva TM4C123GH6PM, User Manual

Page: 319 / 352

USB Controller
24.3.1.24 ROM_USBFIFOConfigSet
Sets the FIFO configuration for an endpoint.
Prototype:
void
ROM_USBFIFOConfigSet(uint32_t ui32Base,
uint32_t ui32Endpoint,
uint32_t ui32FIFOAddress,
uint32_t ui32FIFOSize,
uint32_t ui32Flags)
ROM Location:
ROM_APITABLE
is an array of pointers located at
0x0100.0010
.
ROM_USBTABLE
is an array of pointers located at
ROM_APITABLE[16]
.
ROM_USBFIFOConfigSet
is a function pointer located at
ROM_USBTABLE[17]
.
Parameters:
ui32Base specifies the USB module base address.
ui32Endpoint is the endpoint to access.
ui32FIFOAddress is the starting address for the FIFO.
ui32FIFOSize is the size of the FIFO in bytes.
ui32Flags
specifies what information to set in the FIFO configuration.
Description:
This function will set the starting FIFO RAM address and size of the FIFO for a given endpoint.
Endpoint zero does not have a dynamically configurable FIFO so this function should not be
called for endpoint zero. The
ui32FIFOSize parameter should be one of the values in the
USB_FIFO_SZ_ values. If the endpoint is going to use double buffering it should use the values
with the
_DB
at the end of the value. For example, use
USB_FIFO_SZ_16_DB
to configure an
endpoint to have a 16 byte double buffered FIFO. If a double buffered FIFO is used, then the
actual size of the FIFO is twice the size indicated by the
ui32FIFOSize parameter. This means
that the USB_FIFO_SZ_16_DB value will use 32 bytes of the USB controller’s FIFO memory.
The ui32FIFOAddress value should be a multiple of 8 bytes and directly indicates the start-
ing address in the USB controller’s FIFO RAM. For example, a value of 64 indicates that
the FIFO should start 64 bytes into the USB controller’s FIFO memory. The
ui32Flags value
specifies whether the endpoint’s OUT or IN FIFO should be configured. If in host mode, use
USB_EP_HOST_OUT or USB_EP_HOST_IN , and if in device mode use USB_EP_DEV_OUT
or USB_EP_DEV_IN .
Returns:
None.
24.3.1.25 ROM_USBFIFOFlush
Forces a flush of an endpoint’s FIFO.
Prototype:
void
ROM_USBFIFOFlush(uint32_t ui32Base,
uint32_t ui32Endpoint,
uint32_t ui32Flags)
April 8, 2013 319