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LUMA 500ER
3/2022
values reduce packet overhead but increase the maximum latency. Smaller values improve
latency, but increase the packet overhead, which results in lower average throughput. The
default value is 2000 microseconds.
3.2.5
Forward error correction
Forward error correction makes the communication link more robust and reliable, at the cost of
maximum bandwidth. The following settings are available:
None
: No forward error correction is applied. This enables the highest throughput.
2x bit correction:
A codec that uses 2x redundancy to detect and fix bit errors
1.5x bit correction
: A codec that uses 1.5x redundancy to detect and fix bit errors
Burst (+30) correction:
A codec that can detect and fix burst errors. It adds 30 bytes to
the packet size. Burst correction is supported for serial baud-rates of 9600 bps and
19200 bps. Higher baud-rates can be used only if the average speed of data
transmission is below 19200 bps.
3.2.6
Packet transmit mode
The packet transmit mode specifies the packet-level redundancy used to increase robustness of
the link.
Normal:
No packet-level redundancy is used (default).
4.1 redundant:
adds a 5
th
packet for every 4 packets for redundancy and error
correction.
Dynamic retransmission:
The modem continues to send packets to use the full available
optical bandwidth for the period of time specified in
3.2.4 Data wait time
.
3.2.7
Power level
This parameter specifies the number of emitting LEDs used during transmission (1 = 3 LEDs, 2 =
6 LEDs, 3 = 9 LEDs or 4 = 12 LEDs). The power consumption while transmitting data is 2-5 Watts,
depending on the chosen power level setting.
3.3
Firmware update
A firmware update is required in case a new firmware with additional features is available or if
the serial interface is changed between RS232 and RS485.
confirm that communication with the modem is established as described in
3.1
Connecting the modem
turn off the power supply to the modem (or unplug the SubConn connector, but leave
the serial dongle in the USB port)
