Sierra Wireless FX30S - Set the Serial Port Mode

Sierra Wireless FX30S User Guide
Rev. 7 August 2021 32 41110485
Set the Serial Port Mode
You can configure the serial port in either RS232 or RS-485 mode using Linux
commands.
Note: Before executing these commands, ensure that the UART is set correctly. If the UART is not
set correctly, you will not see serial data. To configure the UART for a particular service, see Enable/
Disable UART on page 75.
You can configure the serial port in either RS232 or RS-485 mode. To change the serial
port mode, use the following Linux command:
rs485.py/sys/devices/platform/msm_serial_hsl.0/rs_mode <NEW
MODE>
where <NEW MODE> is either:
· 0—RS232 (default)
· 1—RS485
For example, to change the mode to RS-485: rs485.py/sys/devices/plat-
form/msm_serial_hsl.0/rs_mode 1
Note: The rs_mode setting is not persistent, and will return to the default setting (RS232) when the
gateway is reset.
Note: In release FX30S 3G R14.0.2.001 and newer, the rs485.py script is available by default in the
root file system in /usr/bin.
For your reference, the contents of the rs485.py script appear below.
#!/usr/bin/env python
import sys
fn = sys.argv[1]
if len(sys.argv) > 2:
value = sys.argv[2]
else:
value = None
ttyFile=open('/dev/ttyHSL0')
if value is None:
sysfsFile = open(fn, 'r')
print sysfsFile.read().strip()
else:
sysfsFile = open(fn, 'w')
sysfsFile.write(value)