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The HelloDevice Pro
Series is configured to
reject IP address of the
PC
Change the remote host access control parameter using serial
or remote console to allow the IP address of the PC
TCP connection with
the other host is
established already
Close established TCP connection or connect later
C.7 Serial communication troubleshooting
Problem
Cause
Action
Serial data are not
transferred by
TCP/IP immediately
Too large inter-character
timeout
Set inter-character timeout with smaller value
Cannot
communicate with
the HelloDevice Pro
Series
Invalid serial port
configuration
Check if serial port configuration of the HelloDevice Pro Series
are the same with that of the serial device
Only serial port#2
of PS400 is not
working (PS400
only)
Serial console is used
Serial port#2 of the PS400 is used commonly for both data port
and serial console port. While serial console is used, data
transfer through serial port#2 is disabled. Close serial console to
use serial port#2 for data transfer.
Invalid data
transferred
Invalid serial port
configuration
Check if serial port configuration is correct.
Invalid serial port
configuration
Check if serial port is set to RS485 Echo or RS485 Non-echo
mode.
RS485 mode is not
working
Terminator resistor is not
attached
The HelloDevice Pro Series has no terminator resistor inside for
RS485 communication. Please attach a 120
Ω
resistor between
Data+ and Data- pins.
Invalid serial port
configuration
Check if serial port is set to RS422 mode.
RS422 mode is not
working
Terminator resistor is not
attached
The HelloDevice Pro Series has no terminator resistor inside for
RS422 communication. Please attach 120
Ω
resistors between
Tx+, Tx- and between Rx+, Rx- pins.