2015-2017 Microchip Technology Inc.
DS00001855E-page 23
USB5744
7.0
DEVICE INTERFACES
The USB5744 provides multiple interfaces for configuration and external memory access. This section details the vari-
ous device interfaces and their usage:
•
•
7.1
SPI Master Interface
The device is capable of code execution from an external SPI ROM. When configured for SPI Mode, on power up the
firmware looks for an external SPI flash device that contains a valid signature of
2DFU
(device firmware upgrade) begin-
ning at address 0xFFFA. If a valid signature is found, then the external ROM is enabled and the code execution begins
at address 0x0000 in the external SPI device. If a valid signature is not found, then execution continues from internal
ROM.
7.2
SMBus Slave Interface
The device includes an integrated SMBus slave interface, which can be used to access internal device run time registers
or program the internal OTP memory. SMBus slave detection is accomplished by detection of pull-up resistors on both
the
SMDAT
and
SMCLK
signals. Refer to
Section 3.4.1, "SPI/SMBus Configuration"
for additional information.
Note:
For details on how to enable each interface, refer to
Section 3.4.1, "SPI/SMBus Configuration"
For information on device connections, refer to
Section 4.0, "Device Connections"
. For information on
device configuration, refer to
Section 6.0, "Device Configuration"
.
Microchip provides a comprehensive software programming tool, Pro-Touch, for configuring the USB5744
functions, registers and OTP memory. All configuration is to be performed via the Pro-Touch programming
tool. For additional information on the Pro-Touch programming tool, refer to Software Libraries within Micro-
chip USB5744 product page at www.microchip.com/USB5744.
Note:
For SPI timing information, refer to
Note:
All device configuration must be performed via the Pro-Touch Programming Tool. For additional information
on the Pro-Touch programming tool, refer to Software Libraries within Microchip USB5744 product page at
www.microchip.com/USB5744.
