3/2022
LUMA 500ER
5
In the top left corner, set the correct COM port and baud-rate. The default setting is
115200 bps, but it may be different if the modems have been configured to another
baud-rate.
Click on "Config mode", and the parameters should become active (instead of greyed
out) if all settings and connections are correct.
The modem is now in configuration mode, which allows you to change the modem
settings. Changed settings will be applied instantly but will revert to the previous
settings after a power cycle. To save the new settings to the modem’s internal flash
memory, click “Save”. To leave configuration mode and return to regular operation, click
“Active mode”.
3.2
Communication settings
3.2.1
Serial baud-rate
This is the baud-rate setting for the communication to the modem over the attached cable. The
baud-rate has to match the selected baud-rate of the host computer or connected device.
Available baud-rates are:
9600, 19200, 38400, 57600, 115200, 204800, 227556, 256000, 512000 bit per second
(default 115200 bps)
When changing the baud-rate of the modem, the baud-rate of the host PC also has to be
changed to the same value.
Note that the changed baud-rate is not permanent until a “Save” command is sent, which is
only possible if the new baud-rate settings work on the modem and the host PC.
3.2.2
Optical baud-rate
This is the speed of the optical link (default: 500000 bps). The optical baud-rate of the two
modems has to be set to the same value. The default value works well in most applications.
3.2.3
Maximum packet size
Min value: 20 ; Max value: 255
The modem collects serial input data from the RS232/485
connection to combine it into a packet. This parameter specifies the maximum packet size.
Packets can be smaller if there is no more input data after a specified time period. Large values
reduce overhead, small values improve latency. The default value is 64, which is a good
compromise.
3.2.4
Data wait time
This parameter specifies the maximum time in microseconds that the modem will wait for
additional data before sending a packet before the maximum packet size is reached. Larger
