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UM1855
Hardware layout and configuration
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2.8.4 Limitations
in
using USB OTG FS port
•
The USB OTG FS port operation as USB host is exclusive with NFC, SWP, LCD glass
module, touch sensing, motor control
•
The USB OTG FS port operation as USB device is exclusive with LCD glass module,
touch sensing, motor control
2.8.5 Operating
voltage
The USB-related operating supply voltage of STM32L476ZGT6 (VDD_USB line) must be
within the range from 3.0 V to 3.6 V.
2.9
RS-232 and IrDA ports
The STM32L476G-EVAL board offers one RS-232 communication port and one IrDA port.
2.9.1 RS-232
port
The RS-232 communication port uses the DE-9M 9-pole connector CN9. RX, TX, RTS and
CTS signals of USART1 port of STM32L476ZGT6 are routed to CN9.
Bootloader_RESET_3V3 and Bootloader_BOOT0_3V3 signals can also be routed to CN9,
for ISP (in-system programming) support. To route Bootloader_RESET_3V3 to CN9, the
R93 resistor must be removed and the JP9 jumper closed (open by default). To route
Bootloader_BOOT0_3V3 to CN9, the JP8 jumper must be closed.
R36
In
Default setting
PC6 is shunted to control the U1 power switch, transiting through the
LCD glass module daughterboard connector.
LCD glass module daughterboard should be in I/O position, with SB2
and SB27 open.
Out
PC6 is disconnected from the LCD glass module daughterboard
connector. It can be shunted to one of alternate resources, either
touch sensing (SB2 closed) or motor control (SB27 closed).
R39
In
Default setting
.
PB12 receives USBOTG_OVRCR signal from U1 power switch,
transiting through the LCD glass module daughterboard connector.
SB3 should be open, R109 in, no smartcard in CN23 slot.
Out
PB12 is disconnected from the LCD glass module daughterboard
connector. It can be shunted to one of alternate resources, either
touch sensing or motor control (SB3 closed).
R38
In
Default setting
.
PB13 receives USBOTG_PRDY signal from CN1 connector, transiting
through the LCD glass module daughterboard connector.
SB6 should be open and no daughterboard inserted in CN13 NFC
connector.
Out
PB13 s disconnected from the LCD glass module daughterboard
connector. It can be shunted to touch sensing (SB6 closed).
Table 8. Configuration elements related with USB OTG FS port (continued)
Element
Setting
Description
