ST STM32F779I-EVAL, Руководство пользователя

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UM2036 Hardware layout and configuration
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6.7 USB OTG1 FS
The STM32F779I-EVAL evaluation board supports the USB OTG1 full speed
communication via a USB Micro-AB connector (CN13) and a USB power switch (U11)
connected to VBUS. The evaluation board can be powered through this USB connector with
5 V DC and with 500 mA current limitation.
A green LED LD7 is lit in one of these two cases:
•
Power switch (U11) is ON and STM32F779I-EVAL works as a USB host
•
VBUS is powered by another USB host when the STM32F779I-EVAL works as a USB
device.
The red LED LD8 is lit when overcurrent occurs.
Note: 1 STM32F779I-EVAL board should be powered by an external power supply when using OTG
function.
Note: 2 JP14 must be removed when using USB OTG FS, as mentioned in Table 10: CAN related
jumpers .
Note: 3 ESDA6V1BC6 (D5) is not entirely securing USB pins against ESD. A negative ESD pulse
on the USB pins can result in possible damage to the microcontroller by driving overcurrent
through the internal diode of the STM32F779NI.
6.8 USB OTG2 HS and FS
The STM32F779I-EVAL evaluation board supports USB OTG2:
•
High speed communication via a USB Micro-AB connector (CN8), USB high-speed
PHY (U8) for high-speed function
• Full speed communication via another USB Micro-AB connector (CN14)
The evaluation board can be powered by these USB connectors (CN8 or CN14) at 5 V DC
with 500mA current limitation.
As several OTG2 FS signals are shared with OTG2 HS ULPI bus, some PCB reworks are
needed, when using OTG2 FS (CN14), as shown in
Table 8 .
A USB power switch (U7) is also connected on VBUS and provides power to either CN8
(with SB21 and SB24 closed and SB22 and SB23 open) or CN14 (with SB22 and SB23
closed and SB21 and SB24 open).
Green LED LD5 (for CN8) or LD9 (for CN14) is lit when either power switch (U7) is ON and
the STM32F779I-EVAL works as a USB host or VBUS is powered by another USB host,
when the STM32F779I-EVAL works as a USB device.
The red LED LD6 is lit when overcurrent occurs.
Table 8. USB OTG2 function configuration
Function Mount Remove
OTG2 HS-CN8 (Default) R107,R113,SB24,SB21 R263,SB22,SB23,SB65
OTG2 FS-CN14 R263,SB22,SB23,SB65 R107,R113,SB21,SB24