Trying to connect MFD8 to Standard Horizon MATRIX AIS

[SIZLAR123]

Hello

I Have pretty low knowledge about Nmea 0183 and i tried many times understanding it without success

I would like to hook up my MFD8 to MATRIX AIS GX2100E (Combined VHF and AIS).

Reason being i want GPS signal (GPS hooked up directly to chartplotter) to the VHF/AIS and from the VHF/AIS i want the AIS and DSC to the chartplotter MFD8.

My question is therefor how would i connect these to units. (See Pictures)
Can i just hook them up somehow or do i need some unit between and so on?

//KR

 

[SIZLAR123]

I belive this is the right way, but as i said im not that good at nmea 0183

 

[Johnny Electron]

To do it correctly you would need some level converters. You will notice that there are not enough negative output wires from the radio. NMEA.ORG requires RS422 level NMEA 0183 which carries a differential signal on the negative. It is not a ground like PC level RS232. You need rs232 to rs422 converters between the radio and the plotter to do it right. While you can fool the system wiring it like you plan it can lead to intermittent data and sometimes damage to your NMEA ports. Many have done it the way you indicate. Since you wired AIS to data 3, you will want to go into the setup wizard and put a CheckMark for AIS on that port so the NN3D will know to process it.

 

[SIZLAR123]

Hi Johnny! Thank you so much for the answer, really thankful for your time and help!
If you have more time and nothing to do i have a second question.

So let say if i would do it the right way.
Do you think i could do it like this (See attachments and uploaded picture).

1st Link: https://www.elfa.se/Web/Downloads/9_/en ... _49_EN.pdf
Page 13-14, Unit I-7520A (RS232-RS422) This is the PDF Instruction.
And this is the official model on official site https://www.icpdas.com/en/product/I-7520A

So i think 2 Units of I-7520A should do the trick.
I think i have done it right and not mixed up RX to TX and vice versa.
Hopefully my drawing is not to messy, inside the red lines is 2 separate unit of I-7520A ,input pins for RS232 and output pins RS422.

//KR

 

[Johnny Electron]

If you match it up with the correct baud rates it should work. I couldn't follow the wiring that well on the converters used. The RS232 wiring connection Seemed to indicate pin 2 is the RXD (Receive data to the converter) but the drawn wires seemed to be going to pin 1 so not completely sure about the plan. You want the DSC output from the radio to go to the input of the one converter and then the converter output goes to the input on the NN3D data port. The GPS data going out the data port would go into the RS422/485 side of the converter and then the converter TXD (Transmit data) would go into the GPS input of the radio. The other converter would be just running the AIS at 38400 coming from the radio into the RS232 side of the converter and then coming out of the converter into the input of the NN3D data port. Ensure that data port used (looks like you plan data 3) is setup for 38400 baud with a checkmark for AIS. The other data port you use to send GPS and receive DSC, you only need to setup the matching baud rate (4800). DSC will automatically process whenever received. Not that for DSC to plot a point on the plotter the radio needs to provide the NMEA 0183 DSC and DSE message. You will need to put the correct output check marks on that NN3D data port to send GPS sentence to the radio (via the converter). These are normally GGA, GLL, VTG, ZDA.