SoM-112ES User Manual
Revision 1.00 © 2018
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Serial Port COM B terminates to a 10-Pin header and can be configured as RS232, RS422, or
RS485 via two jumpers (JB7 & JB8). To select RS232 set jumper JB7 to 232 (this is the default).
For RS4xx set jumper JB7 to 4xx and jumper JB8 to 422 or 485 whichever is desired.
Table 5: Serial Port COM B (HDR3)
Pin
RS-232 10-Pin Header: Description
RS-422/485 10-Pin Header: Description
1
NC
COMB_422/485_TX-
2
NC
NC
3
COMB_232RX
COMB_422/
4
COMB_232_RTS
NC
5
COMB_232TX
COMB_422/
6
COMB_232_CTS
NC
7
NC
COMB_422/485_RX-
8
NC
NC
9
GND
GND
10
NC
NC
Serial Port COM C terminates to a male DB9 connector and is a RS232 port with a full
complement of handshaking lines allowing it to communicate with modems and other devices
requiring hardware flow control (Note actual number of handshake lines is determined be the
SoM)
Table 6: Serial Port COM C (JK3)
Pin
DB9 Connector: Description
1
COMC_232_DCD
2
COMC_232_RXD
3
COMC_232_TXD
4
COMC_232_DTR
5
COMC_232_GND
6
COMC_232_DSR
7
COMC_232_RTS
8
COMC_232_CTS
9
COMC_232_RI
COM E is a serial console to USB device port terminating to a 5-Pin USB micro B connector. This
port offers USB to asynchronous serial date transfers and includes RTD/TXD lines. A Green
activity light is provided for the console interface and located at LD2.
