I have a question about these 4 wires. Are they RS422 or RS232? I understand that NMEA0183 should be RS422, but it appears that sometimes it is not so.

I'm trying to interface these 4 wires to a serial port via a RS422 to Serial converter and its not working.

Thanks for your help!

Views: 293

Reply to This

Replies to This Discussion


Raymarine NMEA 0183 ports are designed to the NMEA 0183 standard, which is essentially RS422.  The AIS500 is manufactured with a DE-9 serial plug to support interfacing the AIS500 with a PC for use with the ProAIS application or other PC application.  In doing so, the BAUD rate will be 38400.  One should not simultaneously interface the 38400 BAUD leads of the AIS500 to a product (ex. MFD) and use the aforementioned DE-9 serial interface, as the AIS500's 38400 BAUD leads are additionally connected to the leads of the DE-9 serial interface.

If using the AIS500's DE-9 serial plug to interface the AIS500 to your serial to USB adapter, then please note that the most cause for communications failures between a PC application and a NMEA 0183 device are

  • incorrect installation of the serial to USB adapter
  • inferior serial to USB adapter design
  • incorrect configuration of the PC application 

Raymarine and many other marine electronics and navigational software application manufacturers recommend or re-brand the SeaLevel Model 2105R and similar SeaLevel serial communications products for customers seeking a serial to USB adapter for use with their NMEA 0183 devices.  Communications between the AIS500 and PC may be tested using the ProAIS applications.  It should also be noted that a serial COM port cannot typically be shared be more than one application unless application software is installed on to PC to support COM port sharing (ex. GpsGate, etc.).

Thanks for that reply. I'm using a FTDIChip RS422 to USB serial converter...here is a description of the wires from the FTDIChip..

Colour Name Type Description
Black GND GND Device ground supply pin.
Brown CTS+ InputClear to Send Control + (B), Input
Red TXD- OutputData – (A) Output
Orange TXD+ OutputData + (B) Output
Yellow RXD+ InputData + (B) Input
Green RTS+ OutputRequest To Send Control + (B), Output
Blue RTS- OutputRequest To Send Control – (A), Output
White RXD- InputData – (A) Input
Grey CTS- InputClear to Send Control input – (A), Input

Which of these wires would I connect to?

Thanks for your help


I would recommend purchasing the serial to USB adapter recommended within my prior response and interfacing the adapter's DE-9 plug to the recommended adapter's socket.  Should you not elect to do so, then you may want to try interfacing the AIS500 to the serial to USB adapter as follows.

  • AIS500 38400 OUT+ to Adapter RXD+
  • AIS500 38400 OUT- to Adapter RXD-
  • AIS500 38400 IN+ to Adapter TXD+
  • AIS500 38400 IN- to Adapter TXD-

As Raymarine AIS receivers and transceivers feature a built in 38400 BAUD to 4800 BAUD multiplexer,

  • data received from an interfaced 4800 BAUD talker will be multiplexed with AIS data and the combined data stream will be transmitted by the AIS receiver/transceiver's 38400 BAUD output port (and corresponding pins of the DE-9 interface)
  • 38400 BAUD data received from a 38400 BAUD talker by the AIS receiver/transceiver's 38400 BAUD input port (and corresponding pins of the DE-9 interface) will be transmitted by the AIS receiver/transceiver's 4800 BAUD output port

As such, should the 4800 BAUD NMEA 0183 output from the E85001 PC/SeaTalk/NMEA 0183 Interface Module (which is interfaced to the SeaTalk bus featuring your ST60 Instruments) be interfaced to the AIS500's 4800 BAUD NMEA 0183 input leads, then the interfaced PC will receive a 38400 BAUD data stream including both AIS and instrument data.  Likewise, should your autopilot's 4800 BAUD NMEA 0183 v2.1 input port be interfaced to the AIS500's 4800 BAUD NMEA 0183 output leads, then 38400 BAUD NMEA 0183 sentences transmitted by the interfaced PC would be re-transmitted by the AIS500 to the autopilot at 4800 BAUD.

Thank you for the detailed very informative response! This is why I buy Raymarine products.

Thanks again

Best regards,


You're welcome.

Reply to Discussion




  • Add Videos
  • View All


  • Add Photos
  • View All

Latest Activity

Torkel Jodalen replied to Torkel Jodalen's discussion AIS950 VSD sentence
"Thanks, I'll be waiting. "
4 hours ago
Tom replied to Tom's discussion ST60+ wind indicator frozen
"I tested the voltage and the results were normal. The wind needle works occasionally so I have to assume its in the instrument now? Possibly the processor? The needle is not rubbing on the glass or instrument backing. This is driving me crazy."
5 hours ago
Neil Langford replied to Neil Langford's discussion Transducer Cross Reference Required / E62007
"Further on this topic, I'm now looking at purchasing the E97 with Clearpulse Sounder circuitry.  With the E97 connected by Seatalk HS to a HS5 network switch, will I be able to share the fish finder images across multiple MFD's…"
7 hours ago
Mark Czerwinski replied to Mark Czerwinski's discussion EV-100 Autopilot Documentation
"I have a few more questions: 1) What is the outer diameter of the wheel drive unit? 2) What is the height of the pedestal bracket? 3) what is the offset of the center of "Slot 1" from the outer circumference of the drive unit? I need this…"
9 hours ago
Profile IconAndré Cavallari, Lorena Hillis, Mike Cole and 27 more joined Raymarine Technical Forum
9 hours ago
Roko posted a discussion

No bottom at all with E120s, CP300, and B164

2 E120s (v5.69) , CP300 (v3.28) , and B164 installed. The CP300 was replaced by Raymarine for my failing DSM300.The performance was poorer from the start after replacing the DSM. Now, it is not providing a bottom value or reading at all. This loss of bottom seems to have gotten progressively worse over the last 2 or so weeks to where it never provides a reading no matter the depth, speed, or water conditions. Unfortunately, this total loss of the depthfinder occurred while on a trip to the…See More
9 hours ago
bill posted a discussion

Dragonfly sonar logging

Someway, a few days ago, I found on Raymarine site the newest update, 10.09 for my DFly 5.7.  It added sonar logging and juiced the gps up to 5 Ghz refresh for the logging I assume.  I believe also it changed the Lighthouse to LH II and 10, might have already been that way, don't recall.  My unit now asks if I want to sonar log and gives the warning.  I can't find where I found this now, almost like it has been pulled back or it never existed (but I have on disk and my MFD works fine with it.…See More
9 hours ago
Russ Lawrence posted discussions
9 hours ago
bill replied to Scott Hughes's discussion GPS problems
"I have had this problem also.  I believe the fix is to go into menu, chart selection, then a list of used or available charts will be shown.  Mouse down to select the chart you have or want to use.  Select and now that chart info…"
9 hours ago
Roko replied to Mike Deto's discussion Disappointing CP300
"Did this ever get resolved?"
10 hours ago
Scott Hughes posted discussions
10 hours ago
Mike Diener posted a discussion

Pathfinder SL70 radar not painting targets

I have a Pathfinder SL70 Series with a D2 18” Radome. Everything seems operational but I cannot get targets to paint on the display. Some other details below including debug codes. I have additional test results if there are specific items of interest. Nothing reported as “failed” on the diagnostic tests. Can anyone help me figure out what’s going on?  I bought the boat used with this equipment so I have no history on the radar. Thanks Scanner Build STD           …See More
10 hours ago
Georege Brown posted a discussion

VHF510 Handheld

Have a Apelco VHF510 waterproof handheld.  Had not been used for a while.  Charged up battery and attempted contact with another VHF station without success.  Cannot receive either.  Can hear microphone click when PTT is pressed.  Battery seems to be in good shape.  Any suggestions? Is unit too old to pursue repair if necessary?Thanks,George See More
10 hours ago
Denis Marceau posted a discussion

rd 218

is the rd 218 compatible with old RL displays seriesSee More
10 hours ago
Moderator - Raymarine, US replied to Robert Horn's discussion C125, Lighthouse II, 11.26 fails to display Navionics charts
"Bob, Again, I can't explain why it could have worked on the dealer's display, as the encryption isn't designed to support the action that you undertook.  I would recommend speaking to Navionics about the best way to proceed in…"
11 hours ago
Robert Horn replied to Robert Horn's discussion C125, Lighthouse II, 11.26 fails to display Navionics charts
"The point is that we want to do the Great Loop and therefore I purchased the US & Canada upgrade. But with 2GB I can barely fit the Gulf Coast on the chip. With the 16GB chip I can do all of the areas that cover the Great Loop. So if I can only…"
11 hours ago

© 2014   Created by Moderator - Raymarine, US.   Powered by

Badges  |  Report an Issue  |  Terms of Service