STI STM32091C-EVAL, User Manual

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UM1817 Hardware layout and configuration
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The RS-485 communication is supported by the RS-485 transceiver ST3485EBDR which is
connected to pin 4 and pin 9 of D-type 9-pins connectors CN9 (share same connector with
USART1), see
Table 11 .
2.9 Touch sensing buttons
Two touch sensing buttons are supported on the STM32091C-EVAL evaluation board and
they are connected to three capacitive sensing channels (PD[12:14]) in group8 with active
shield being connected to two capacitive sensing channels (PB11 and PB12) in group6 (see
Table 12 ).
Table 10. RS-232 and IrDA related jumpers
Jumper Description
JP13
RS232_RX is connected to RS-232 transceiver and RS-232 communication is
enabled when JP13 is set as shown to the right (Default setting):
RS485_RX is connected to RS-485 transceiver and RS-485 communication is
enabled when JP13 is set as shown to the right:
IrDA_RX is connected to IrDA transceiver and IrDA communication is enabled when
JP13 is set as shown to the right:
Table 11. RS-485 related solder bridges
Jumper Description
SB15, SB18
The external failsafe biasing are enabled when solder bridges SB15 and SB18 are
closed
Default Setting: Not fitted
SB19
The bus termination is enabled when solder bridge SB19 is closed.
Default Setting: Not fitted
SB16
The AC termination is disabled when solder bridge SB16 is closed for high baud rate
communication.
Default Setting: Not fitted
RS
23
2
RS
48
5
Ir
D
A
RS
232
RS
485
Ir
D
A
RS
23
2
RS
48
5
Ir
D
A