ShipModul MiniPlex-2Wi User manual

MiniPlex-2Wi NMEA 0183 multiplexer
Manual
ShipModul
Marine Electronics
MiniPlex-2Wi, V1.0
Firmware V3.17.x
Art.no.: 1125
Man. rev. A
© CustomWare, 2012

2
Introduction....................................................................................................................... 3!
Talkers and Listeners ....................................................................................................... 3!
The Multiplexer................................................................................................................ 3!
The MiniPlex-2Wi ............................................................................................................. 4!
Connections....................................................................................................................... 5!
NMEA Signals .................................................................................................................. 5!
NMEA Listener Ports/Inputs............................................................................................... 5!
NMEA Talker Ports/Outputs ............................................................................................... 5!
Combining Ports .............................................................................................................. 6!
SeaTalk .......................................................................................................................... 7!
USB Port ........................................................................................................................ 7!
WiFi Interface.................................................................................................................. 8!
Power Supply .................................................................................................................. 8!
Indicators.......................................................................................................................... 8!
Driver Installation............................................................................................................... 9!
Windows 7 Installation ..................................................................................................... 9!
Windows 2000/Vista/XP Installation ................................................................................. 14!
Mac OS X Installation ..................................................................................................... 14!
Data Throughput .............................................................................................................. 15!
Configuration ................................................................................................................... 17!
Menu ........................................................................................................................... 18!
Controls ....................................................................................................................... 19!
Host Settings.............................................................................................................. 19!
Manual NMEA input ..................................................................................................... 19!
Input Overflow ........................................................................................................... 19!
Read Configuration...................................................................................................... 20!
NMEA Inputs/Outputs .................................................................................................. 20!
Options...................................................................................................................... 22!
NMEA Conversions. ..................................................................................................... 23!
Sentence Filtering & Routing ........................................................................................... 25!
Resetting the multiplexer................................................................................................ 27!
Firmware Update .............................................................................................................. 28!
Mounting......................................................................................................................... 28!
Technical Reference .......................................................................................................... 29!
NMEA Glossary .............................................................................................................. 29!
Talker ID’s ................................................................................................................. 29!
Sentence formatters.................................................................................................... 29!
Translated SeaTalk datagrams......................................................................................... 31!
Firmware Update Error messages..................................................................................... 32!
MPX-Config INI file format .............................................................................................. 33!
Proprietary NMEA Sentences ........................................................................................... 34!
CF – Configuration ...................................................................................................... 34!
CFQ – Request current configuration.............................................................................. 35!
CN - Channel Number indicator ..................................................................................... 35!
DR – Default Route ..................................................................................................... 35!
DRQ – Request Default Route ....................................................................................... 36!
FL – Filter .................................................................................................................. 36!
FLQ – Request Filter List .............................................................................................. 37!
ID – Talker ID ............................................................................................................ 37!
IDQ – Request Talker ID’s............................................................................................ 37!
LDR – Loader message ................................................................................................ 37!
OV – Overflow ............................................................................................................ 37!
RESET – Reset the multiplexer...................................................................................... 38!
SP – Speed ................................................................................................................ 38!
SPQ – Request Speed .................................................................................................. 38!
TAG Block .................................................................................................................. 38!
VER – Get Version....................................................................................................... 39!
WI – Wireless control................................................................................................... 39!
Technical Specifications .................................................................................................. 42!
Declaration of Conformity .................................................................................................. 43!

3
Introduction
The MiniPlex-2Wi is an NMEA multiplexer that enables the connection of multiple NMEA 0183
instruments to each other and a computer and/or wireless devices. It is developed to solve a
fundamental problem with the NMEA 0183 standard.
The NMEA 0183 standard defines a communication protocol that enables navigation instruments to
exchange data with each other. A compass can send a bearing to a radar to enable a north-up
display, a GPS can send cross-track information to an autopilot in order to steer a programmed
course. The same GPS can also send information to the radar at the same time since the NMEA
0183 standard specifies that one device must be able to send data to up to four other devices.
NMEA data is made up of short text messages with a strict format called sentences and are human-
readable.
Talkers and Listeners
Communication using the NMEA 0183 protocol involves at least one
device that sends NMEA sentences and another device that receives
NMEA sentences. By convention, a sending device is called a talker
while a receiving device is called a listener. The picture on the right
shows such a minimal system: a gyrocompass sending heading
sentences to a radar.
The NMEA 0183 standard specifies that a talker should have enough driving capability to talk to
four listeners. This is as easy to achieve as telling a story to an audience of up to four people. The
only requirement is to talk loud enough.
The picture left below shows such a situation.
It gets complicated when several talkers must send data to one listener as shown in the picture on
the right. Unless that listener has multiple inputs, this is not possible without help. Simply
connecting talkers to one listener as shown is like four persons simultaneously telling you a
different story. You can make neither head nor tail of it. In electronics terms: the outputs of the
talkers will effectively short-circuit each other and the sentences they transmit will be corrupted.
This is where a multiplexer offers the solution.
The Multiplexer
A multiplexer, sometimes called ‘combiner’, has multiple inputs, each acting as a single listener
connected to a talker (the instruments). It has one or more outputs that are able to talk to multiple
listeners. These outputs deliver the combined data from the inputs.
A clever piece of software inside the multiplexer reads the NMEA sentences that are received on
the inputs simultaneously and stores them into queues, one for each input. Another part of the
software retrieves the sentences from the queues, one at a time, and sends them to the outputs of
the multiplexer. This way, four incoming streams of sentences are combined into one single
stream.
GPS
PC
VHF
Radar
Auto-
pilot
PC
GPS
Depth
Wind
Log
Gyro Radar

4
The picture below shows a typical setup with a multiplexer combining data from a wind instrument,
a compass and a GPS. This data is forwarded to a tablet and an autopilot using two different types
of outputs: an NMEA talker port called ‘Out1’ and a WiFi interface. The multiplexer forwards the
received NMEA sentences to the tablet and the autopilot at the same time.
The WiFi connection to the tablet is actually bi-directional: the tablet acts as a listener and a talker
at the same time. It receives NMEA sentences from the instruments to be processed by navigation
software on the tablet. This software can generate NMEA sentences to control an autopilot. These
sentences are sent to the multiplexer and forwarded to the autopilot. They can be combined with
the sentences received from the other navigation instruments.
The picture also shows a computer in light grey that is connected to the USB port on the
multiplexer. The MiniPlex-2Wi also has a USB port with the same function as the WiFi interface.
This allows you to connect a second (fixed) computer while having the freedom of moving around
with your laptop, PDA, tablet or smartphone having access to the same navigation data as the
fixed computer.
The USB port is also used to update the firmware of the multiplexer and to configure the WiFi
interface. These tasks cannot be performed using the WiFi interface.
The MiniPlex-2Wi
The MiniPlex-2Wi is a multiplexer with four NMEA inputs (listener-ports), two NMEA outputs (talker-
ports), a WiFi interface and a USB port to connect to a computer. The multiplexer combines NMEA
data that is received on the listener ports In1 to In4 and sends this data to talker ports Out1 and
Out2,to the WiFi interface and to the USB port. The WiFi interface and the USB port are also used
to send data from a computer to the multiplexer to be forwarded to Out1, as well as to send
commands to configure the multiplexer.
Every NMEA input on the MiniPlex is galvanically isolated, sometimes called opto-isolation because
of the use of opto-couplers for isolation. An opto-coupler is a small device that transports
information by means of light instead of electricity.
A galvanically isolated input prevents unwanted currents to flow between instruments and the
multiplexer. These currents can damage equipment or interfere with radio signals and should
therefore be avoided. Galvanically isolated inputs are required by the NMEA standard.
The USB port of the MiniPlex is also galvanically isolated, which isolates the computer from the
navigation network and protects it against potential damage caused by ground loops or voltage
spikes.
Both NMEA outputs can drive up to four listeners each. Flexible routing options allow you to specify
which NMEA sentences are sent to these outputs.
Besides the basic functionality of combining NMEA data from multiple sources, the MiniPlex offers a
range of features to manage NMEA data like Sentence Filtering and Routing, Input Priority with
automatic switchover, testing of data integrity, Talker ID modification and SeaTalk®to NMEA
translation.
The MiniPlex can seamlessly be integrated into an existing Raymarine SeaTalk network when
SeaTalk mode is enabled. This mode changes one NMEA listener port into a SeaTalk input. When
connected to a Raymarine SeaTalk network, the multiplexer will translate SeaTalk data into NMEA
sentences and combine these with NMEA sentences that are received on the other listener ports.
Only one SeaTalk input is needed since the SeaTalk bus is a single-cable system that connects all
instruments together through one single cable. SeaTalk to NMEA translation in the MiniPlex works
only one-way. No NMEA sentences are converted into SeaTalk, the multiplexer just listens on the
SeaTalk bus.
Wind
Comp-
pass
GPS Autopilot
Multiplexer
In 1
In 2
In 3
USB
Out 1
PC
Tablet
Wifi

5
Connections
NMEA Signals
Although the NMEA 0183 standard very clearly specifies the signal names, voltage levels and
connection methods, the reality is far from this ideal world.
The most important property of an NMEA port is that the connections or wires are labelled ‘A’ and
‘B’ and that it uses a differential signalling scheme. This means that data is transmitted on both
wires, but in ‘opposite direction’. Both wires are driven between 5V and 0V and opposite of each
other. This means when A is 5V, then B is 0V and vice versa. The advantage of this signalling
scheme is that it is very insensitive to electrical interference. NMEA ‘A’ and ‘B’ are often labelled as
NMEA ‘+’ and ‘-’ respectively. When connecting devices, simply connect NMEA ‘A’ to NMEA ‘A’ or
NMEA ‘+’ and NMEA ‘B’ to NMEA ‘B’ or NMEA ‘-’.
Things get complicated when manufacturers don’t follow the NMEA 0183 standard, which is very
often the case. Many devices have an NMEA port, which is really an RS-232 port. The only
resemblance with the NMEA standard is the format of the data transmitted. Electrically, they are an
entirely different world. The used signal names differ wildly and often lead to confusion. When a
device has a listener port with connections ‘Data In’ and ‘Data Return’ it is not clear whether this
input is galvanically isolated or ‘Data Return’ is simply another name for ‘Signal ground’
As opposed to the NMEA standard, many devices use a single-ended signalling scheme where data
is transmitted on one signal wire while a power/signal ground presents the return path for data.
Single ended devices often have connections named as TX and Gnd (transmit and ground) on the
talker port and RX and Gnd (receive and ground) on the listener port. Also used are Data Out, Data
In and Signal Ground. Mix these with ‘standard’ NMEA connections and confusion is imminent!
In general it is safe to connect a single ended talker port to a differential listener port. Connecting
a differential talker port to a single ended listener port however is less obvious. When NMEA ‘B’ of a
talker port is connected to the signal ground of a listener port, the ‘B’ signal is effectively short-
circuited to ground. A properly designed talker port can handle this abuse but it will result in fairly
high currents in long cables, which in turn leads to severe interference on SSB radios and possibly
on VHF radios too. In the worst case, the talker port will be destroyed.
To overcome this problem, the MiniPlex multiplexers provide a Com terminal on each talker port in
addition to the ‘A’ and ‘B’ terminals. This ‘Com’ terminal is similar to a signal ground. To connect a
talker port of the MiniPlex to a differential NMEA listener port, use the ‘A’ and ‘B’ terminals. Use the
‘A’ and ‘Com’ terminals to connect to a single-ended or RS-232 listener port.
NMEA Listener Ports/Inputs
The multiplexer has four listener ports or inputs, In 1 to In 4. Each listener port should be
connected to one instrument only. These inputs are completely floating and galvanically isolated
from the multiplexer, as specified in the NMEA 0183 standard.
Connect the Aand Bterminals of the listener port on the multiplexer to the Aand Bterminals of
the talker port on the instrument. These terminals may also be labelled as Data+ and Data-, TX+
and TX-, Out+ and Out–or ve+ and ve-.
Some instruments have single ended talker ports, with only one data terminal. Connect this
terminal to the Aterminal on the multiplexer, and connect the ground of the instrument to the B
terminal on the multiplexer. The instrument’s data ground is often combined with its power supply
ground.
NMEA Talker Ports/Outputs
Both talker ports or outputs can be connected to up to four instruments. Connect the Aand B
terminals of the talker port on the multiplexer to the Aand Bterminals of the listener port(s) on
the instrument(s). These terminals may also be labelled as Data+ and Data-, RX+ and RX-,
Out+ and Out–or ve+ and ve-.
Multiplexer
In A
In B
Instrument
Out A/+
Out B/-
Differential
Multiplexer
In A
In B
Instrument
TX/Out
Ground
Single ended

6
Some instruments have single ended listener ports, with only one data terminal. Connect this
terminal to the Aterminal on the multiplexer, and leave the Bterminal on the multiplexer
unconnected. Connect the ground of the instrument to the Com terminal on the multiplexer. The
instrument’s data ground is often combined with its power supply ground.
The shield terminals on the multiplexer (Shld) can be connected to the screen/shield of the cable if
available. This should always be done on one end of the cable only, preferably on the end that is
connected to a talker port.
Combining Ports
It is sometimes necessary to combine a listener and talker port of the multiplexer to connect to an
instrument. One of the most commonly used combinations is the connection of a GPS to the
multiplexer. While some GPS receivers have properly designed NMEA ports, many only have an
RS-232 port which is single ended with three terminals: TxD (data out), RxD (data in) and Ground.
The picture below shows how to connect such a GPS to the multiplexer.
Instrument
In A/+
In B/-
Multiplexer
Out A
Out B
Differential
Instrument
RX/In
Ground
Single ended
Com
Multiplexer
Out A
Out B
Com
Instrument
In A/+
In B/-
Multiplexer
Out A
Out B
Multiple differential and
single ended listeners
Com
Instrument
In A/+
In B/-
Instrument
RX/In
Ground
GPS
TxD/Out
Ground
RxD/In
Multiplexer
In A
In B
Out A
Out B
Com
Connecting a GPS with a serial port
to the multiplexer

7
SeaTalk
SeaTalk®is a proprietary protocol developed by Raymarine®. This protocol is used for
communication between Raymarine navigation instruments like the ST40, ST50 and ST60 series.
To be able to use these instruments with commonly available navigation programs or to feed their
data into other non-Raymarine instruments, the SeaTalk data needs to be translated into NMEA.
Even Raymarine's own navigation software, Raytech Navigator, needs this translation.
The MiniPlex can be directly connected to a SeaTalk network. It will translate all SeaTalk data
required for navigation into NMEA sentences. Input In 4 can be set to SeaTalk mode
(SeaTalk -> NMEA) and should be connected as shown below:
Note that the red and yellow wires are used! The shield of the SeaTalk cable is not connected to
the multiplexer.
USB Port
The USB port connects the multiplexer to a computer or a USB hub with the supplied cable. The
supplied driver provides a virtual COM port to allow navigation software to communicate with the
multiplexer. The USB port is bi-directional: the multiplexer sends NMEA data to the computer and
the computer can also send NMEA data back to the multiplexer. This data can be routed to
NMEA Out 1 and NMEA Out2.
The USB port is galvanically isolated from the multiplexer to prevent ground loops and excessive
currents that could otherwise destroy the multiplexer or the USB port of the connected computer.
The USB connection supports flow control, which is needed when waypoints and routes are sent
from the computer to a GPS through the multiplexer. While normal NMEA sentences are sent at
regular intervals, waypoints and routes are sent ‘in one go’ without any pause between these NMEA
sentences. This fills up the queue in the multiplexer almost immediately after which the multiplexer
discards the remaining waypoints and routes. The GPS now only receives a few waypoints and
partial routes.
Flow control prevents this from happening. When the queue in the multiplexer is almost filled, the
multiplexer signals the computer to stop sending data. When the queue is sufficiently emptied, the
multiplexer signals the computer to continue. This requires a special setting in your navigation
software, which is mostly called ‘Flow Control’. This setting can mostly be found in the port settings
of your software. Set the Flow Control to Hardware or CTS/RTS. This Hardware flow control is
virtualized over the USB connection. Do not use Xon/Xoff flow controls since this uses special
characters instead of a (virtual) signal. These characters are not part of the NMEA standard and
therefore ignored by the multiplexer.
SeaTalk cable
Multiplexer
In 4A
In 4B
Red
Yellow
Connection to a SeaTalk network

8
WiFi Interface
Through its WiFi interface, the MiniPlex-2Wi can communicate with a wireless device such as an
iPad, iPhone, an Android based smartphone or tablet, a PC or a Mac. The multiplexer creates a
wireless Access Point 820.11b+g interface with the following parameters:
SSID (name): MiniPlex-2Wi:xx:xx
IP address: 10.0.0.1
Port: 10110
Protocol: TCP
The xx:xx’s are the last two bytes of the MAC address of the multiplexer as printed on the serial
number sticker. This uniquely identifies a MiniPlex-2Wi from similar devices.
A wireless device that connects to the MiniPlex-2Wi will get an IP address from the built-in DHCP
server. It is not necessary to set a fixed IP address in your device.
Configure your navigation software to connect to IP address 10.0.0.1 and port 10110 using the TCP
protocol.
The MiniPlex-2Wi supports only one connection WiFi connection at a time. The WiFi interface and
the USB port operate simultaneously and with the same priority. This allows an on-board fixed
computer to be connected simultaneously with a wireless device.
The WiFi interface cannot be used to update the firmware of the MiniPlex-2Wi or to configure the
WiFi interface using $PSMDWI commands (see the Technical Reference, Proprietary NMEA
Commands). All this has to be done using the USB interface.
Power Supply
The multiplexer must be powered from an externally supplied DC voltage from 8 to 35V. The power
supply connection is protected against reversed polarity.
Indicators
The multiplexer has three LEDs. The green LED indicates the reception of valid NMEA data on the
listener ports or from the network. It only blinks on valid NMEA sentences that start with a ‘$’ or ‘!’
and end with a CR and LF character, thus indicating a proper connection and polarity of the
connected instrument. In case of a reverse polarity of a connected talker, the green LED will not
blink. The green LED also blinks every two seconds to indicate that power is present and it is
operational. This blink is slightly dimmer than a blink on data reception.
The red LED indicates a queue overflow, in case more data is received than can be transmitted.
See section ‘Data Throughput’ for options to resolve this situation.
During a firmware update, the red LED will be lit continuously when the update is in progress while
the green LED blinks on the reception of firmware data from the computer. This will give a visual
indication of the update process.
The yellow led indicates the status of the WiFi connection: and has three possible states:
Off: The MiniPlex is configured to connect to a WiFi Access Point but the connection failed.
On: The WiFi Access Point is active and ready for use.
Blinking: An application has connected using TCP.

9
Driver Installation
To use the MiniPlex-2Wi with your computer using the USB interface, a device driver needs to be
installed. This driver creates a virtual COM port, which can be opened with any navigation software
just like any other COM port. Drivers are supplied for Microsoft Windows (Windows 2000, Windows
XP, Windows Vista, Windows 7) and Apple’s Mac OS X.
If you plan to use the MiniPlex-2Wi using the WiFi interface only, no driver needs to be
installed. Firmware updates however can only be loaded using the USB interface.
Windows 7 Installation
When the MiniPlex is connected to the computer for the first time, Windows will automatically
download the most recent drivers from the Windows Update Service when an Internet connection is
available. Without connection to the Internet, Windows will eventually tell you that the ‘Device
Driver software was not successfully installed’.
The following procedure allows you to install the drivers for the MiniPlex manually.
Open Control Panel -> System and Security -> Device Manager.
In the Device Manager, there will be a ‘ShipModul MiniPlex-2Wi’ listed under ‘Other Devices’ as
shown in the picture.
Right-click on the MiniPlex entry and choose ‘Update Driver Software...’ from the menu that
appears. This will open the following window:

10
Choose ‘Browse my computer for driver software’. In the following window, choose the location of
the driver (the ‘\USB Driver\Windows’ subfolder on the MiniPlex Driver & Utility CD) and press
‘Next’.