HYDROMEA Luma X User manual

a fast, long-range, optical underwater communication system
Manual
Ver 1.4
3/2022

2 LUMA X 3/2022
Contents
1 Introduction ............................................................................................................................ 4
2 Operation ................................................................................................................................ 4
2.1 Initial setup guide ............................................................................................................. 4
2.1.1 Windows 10 setup .................................................................................................... 5
2.1.2 LUMA X setup ............................................................................................................ 6
2.1.3 Setting the IP address ............................................................................................... 7
2.1.4 Setting modems to Active Mode .............................................................................. 8
3 Modem configuration ............................................................................................................. 9
3.1 LUMA X web configuration menu .................................................................................... 9
3.1.1 Main page ............................................................................................................... 10
3.1.2 Parameters page ..................................................................................................... 10
3.1.3 Status page .............................................................................................................. 12
3.1.4 IP address change page........................................................................................... 13
4 Modem configuration and testing using LumaConf ............................................................. 14
4.1 LumaConf parameters .................................................................................................... 17
4.2 Firmware upgrade and factory reset ............................................................................. 18
4.3 Communication test ....................................................................................................... 19
4.4 Recording a log file ......................................................................................................... 21
4.5 Visualizing a log file ........................................................................................................ 21
5 Maintenance ......................................................................................................................... 21
6 API ......................................................................................................................................... 22
6.1 API parameters ............................................................................................................... 22
6.2 Usage examples .............................................................................................................. 24
7 Electrical and software Characteristics ................................................................................. 25
8 Mechanical Characteristics ................................................................................................... 26
9 Errata ..................................................................................................................................... 28

3 LUMA X 3/2022
WARNING:
 bright LED light source, do not look directly at emitter
 a few people may experience epileptic seizures when
viewing flashing lights

4 LUMA X 3/2022
1 Introduction
The LUMA X is an optical modem for fast, reliable wireless underwater communication. Each
LUMA X is a full transceiver and thus capable of half-duplex communication (transmission and
reception).
2 Operation
Note: while submerging the LUMA X, a small number of bubbles may come out of the
pressure compensation vent at the connector end of the modem. When LUMA X is back on
the surface a small amount of water may come out of the vent.
2.1 Initial setup guide
Note: before first operation, the LUMA X needs to be configured.
The following sections describe the initial network setup and LUMA configuration.
On factory default, LUMA X has the default IP address 192.168.102.101, and will send telemetry
to a host computer that has the IP address 192.168.102.100. The first step is thus to set the
host computer to this address for the initial configuration.
For the purpose of initial setup and testing, the default network configuration and IP addresses
are used, as shown in Figure 1. For operational use, the IP addresses of the LUMA X modem and
the computers connected to them can be configured differently to suit individual network
requirements.
Note: As the LUMA modems form a bridge, they should not be connected to the same cabled
network (i.e. do not plug both modems into the same switch). Doing so may lead to a loop in
the network, where one LUMA picks up traffic from the other LUMA and feeds it back to the
switch, flooding the network with packets. The modems should be connected to two separate
cabled networks as shown below.
Figure 1: Typical initial test setup

5 LUMA X 3/2022
2.1.1 Windows 10 setup
On Windows 10 this is set up as follows:
 go to → Settings → Network & Internet → Ethernet (in left column) → Network and
Sharing Center (in right column) → Change adapter settings (in left column) → right click
on Ethernet adapter → Properties → select Internet Protocol Version 4 (TCP/IPv4) →
Properties
 set the address as shown in Figure 2
Verifying the IP address setting:
 Open a command line: → Windows PowerShell
 Type: ipconfig /all
Figure 2: Windows 10 network settings

6 LUMA X 3/2022
 You should see the IPv4 address setting shown in Figure 3
Figure 3: IPv4 address settings for LumaConf
On the remote PC, repeat the procedure, but set the IP address to 192.168.102.103.
2.1.2 LUMA X setup
Once the host computer’s IP address is set correctly the connection to the LUMA X can be
tested.
 Connect only one LUMA X to a computer via an Ethernet connection using Hydromea’s
power/data cable.
 Connect the LUMA X to a suitable supply voltage (12 V – 36 V) using Hydromea’s
power/data cable.
 (Optional step) To test that the IP address has been set correctly, the computer should
now be able to ping the LUMA X on its default IP address 192.168.102.101 and the
modem should respond to it.
o Windows 10: Open a command line: → Windows PowerShell
o enter ping 192.168.102.101

7 LUMA X 3/2022
 Open a browser, and enter 192.168.102.101 into the address field. The LUMA X web
interface main page should appear (see Figure 4)
All LUMA X are factory-set to boot-up into config mode and their factory-set IP address is
192.168.102.101.
In order to use several LUMA X within the same network for configuration and testing, they
need to be set to differing IP addresses. Please follow the steps in the following section to
change the IP address of the second modem.
2.1.3 Setting the IP address
For the initial test, modem (1) can remain at the default IP address. The other modem (2) has to
be set to a new IP address that is unique within the subnet. For the initial example, we use
192.168.102.102.
 Plug in only modem number (2) and navigate your browser to 192.168.102.101
 Click on the menu item “IP change”
 Enter the new IP address 192.168.102.102 (for the second modem)

8 LUMA X 3/2022
 Click “Set”. The new IP address is now temporarily applied, and the page will reload
showing the new IP address:
 To store the new setting to flash memory, click “Save”. The modem is now set to the
new IP address.
2.1.4 Setting modems to Active Mode
The LUMA X has two modes of operation: config and active.
The config mode is the inactive mode and the modem will not forward data between the
ethernet cable and the optical interface.
After setting the configuration, LUMA X can be switched to active mode. It will now behave as a
bridge device, forwarding any traffic from the cable side via the optical link. This effectively
connects the networks on both sides, comparable to a cabled connection between two
switches or end devices.
For purposes of the initial test, we will leave all parameters on default values, and switch the
two modems to “active” to establish a link.
 Plug in the first modem and power it up, load the web interface (as previously)
 Click on the menu item “Parameters”
 Change “Default start state” to “Active”
 Click “Set”
 Click “Save”
 Unplug the modem, repeat all steps with the second modem.
 At the next power-up, the modems will operate in “active” mode.
The modems are now ready. Connect the first modem to the Operator PC, and connect the
second modem to a remote PC (e.g. a second laptop, or an ethernet-capable remote device).
The operator PC should be set to IP address 192.168.102.100. The remote PC should be set to
IP address 192.168.102.103 (this IP address is given as an example for the initial setup – it can
be chosen freely within the same subnet).

9 LUMA X 3/2022
Power up the modems on both sides. The boot-up takes up to 10 seconds.
On the operator PC, open a Shell, and type:
ping 192.168.102.103
If everything is configured correctly, the modems will visibly flash with blue light, and the ping
will show the response from the remote PC.
The optical link is now ready and will forward any ethernet traffic from one side to the other
side.
Note that ambient light, artificial light sources (fluorescent office lighting, LED lamps, screens,
sunlight) may interfere with the optical channel and disrupt communication. If a link cannot be
established, try to turn of lights, or cover the modems with an opaque sheet of cardboard or
cloth while ensuring line of sight between the modems. Ideally the modems should be
separated by at least 1 meter, as the receiver may saturate at very close range.
3 Modem configuration
This chapter will describe the modem configuration in detail.
There are two ways to configure LUMA X, the built-in web interface as well as LumaConf, an
external program. The web interface is the preferred way to configure LUMA X. LumaConf
offers some additional test features that provide several performance metrics for a two-modem
connection.
This chapter details the configuration of LUMA X using the web interface and chapter 4 explains
the configuration via LumaConf.
3.1 LUMA X web configuration menu

10 LUMA X 3/2022
3.1.1 Main page
Figure 4: main page of the web-based configuration-UI
This page provides information about the current revision of the hardware, firmware and API. It
also provides the firmware’s SHA and the unique processor ID.
3.1.2 Parameters page
Figure 5: parameter page of the web-based configuration-UI
This is the main configuration page for the LUMA X. Hovering over the “?” next to each
parameter provides a short description.