All multiplexers have a mode of operation called Simulation Mode. This mode is very useful to learn about the capabilities of the multiplexer. Before installing the multiplexer in your boat, you can power the multiplexer through a USB cable and check the connection between the multiplexer and the apps that receive data.
In simulation mode, the multiplexer ignores all the data that may be arriving at any input. Instead, it will use a fictitious set of data for P1 and P2 which can be directed to wifi (UDP or TCP), to the serial output port P3 or P5 and, in the case of the Nmea3Wifi multiplexer to the SeaTalk1 bus. If P1 is set, GPS data for the location of the own boat is generated. Time will be October, 1, 2019 by 12:00. Position is in the marina of Mytiline, Lesvos, Greece, about N39 5.85 and E26 33.46. Depth is 4 meters, water temperature is 19.3 Celsius, wind is about 10 kts from NE and velocity is zero as the boat is moored. The set contains 25 Nmea0183 sentences which are transmitted, cyclically at a rate of 7 sentences per second. If P2 is set, AIS data is also simulated. It will show 2 boats moored alongside, BEAUMARIS and GALEAO, in the same marina. The set contains 14 AIS Nmea0183 sentences which take about 28 seconds to transmit. Then they will repeat forever. The green leds will blink as if the sentences were arriving at P1 and P2.
Using the Nmea2Wifi as an example we enter in Simulation Mode by checking the radio button "Simulation Mode" and pressing SET in the main settings web page. The multiplexer checks if there are errors in your settings. If there are errors, the page is repeated with errors signalled in red colour. If there are no errors, the following page is presented:
The led for port P1 blinks rapidly (about 7 sentences per second) and the led for port P2 blinks once in 2 seconds since there are only 2 AIS targets and because they are moored (not moving) their messages are sparse. Here is a screen shot of what we get in SeaWi Android App:
The black boat is the owner boat (supposedly Margarida in pontoon C) and the brown and blue boats are supposedly GALEAO and BEAUMARIS (these were the names of Luis previous boats!). If instead of SeaWi, you use Navionics Boating you get the following picture:
The settings for the Multiplexer and Navionics were UDP at port 2000. And, of course P1>UDP and P2>UDP both checked!
Using Simulation Mode you can set the proper operation of the multiplexer and the app that receives data. Here is what you get in ISailor: