Another Fuel/Speed / GPS question

[sandiegosteve]

There seem to be a number of wiring questions already in here, but I ether don't get it, or I've got a bad unit. My goal is to get GPS information to my CommandLink Fuel/Speed square gauge. The pito sensor works, but with the local kelp, it seems to get clogged a lot.

Square Fuel / Speed Command link Gauge
2007 F115 w/ CommandLink network.
Lowrance HDS 8 (NMEA 0183 GPS)
ICOM M422 VHF


My VHF is set up via the NMEA 0183 RX and TX wires from the Lowrance. I get the "GPS" icon, so I know the HDS unit does send it out. The VHF has RX+, RX-, TX+ and TX- where the Gauge just has RX + and RX -.
My goal is to have both hooked up to the GPS TX from the Lowrance.

I'm not getting lucky with the Yamaha fuel gauges. I expect to see the "GPS" icon lit when it has a good connection.


The Lowrance HDS has 2 NMEA 0183 output options (RS-422 and RS-232). I can also select output baud rate for them; 4800 works for the VHF, so I assume that is be best. Does it matter for the Yamaha gauge? I've been useing RS-422 @4800 baud which works for the VHF.


Testing: I know the VHF <-> GPS works, so I'm trying to get the Yamaha gauge to work. I assume I connect the white (+) wire from gauge to the Yellow TX (+) from the Lowrance and the Blue (-) wire from the gauge to the Blue (-) wire from Lowrance. Right? I saw another post that almost makes it look like I only want 1 wire (white +) attached...??? Would the Blue (-) literally be a ground?

If I can get the GPS -> the Yamaha gauge, can I share the 0183 connection via a splice? The NMEA 0183 spec says 1 transmitter can broadcast to 3 devices, but I don't know if I need a special hub for that.

Step 1 is to get the GPS signal to the gauge. I did use the soft menu to enable GPS (hod set for 4 seconds, use mode to enable).


I appreciate any tips!



Lowrance wires for NMEA 0183 via RS-422
Yellow TX (+)
Blue TX (-)
Orange RX (+)
Green RX (-)
Shield (gnd)




Lowrance Wire options for NMEA 0183 via RS-232
Com 1
Yellow TX
Orange RX
Shield Ground

Com 2
Blue TX
Green RX
Shield Ground

[boats.net]

On the wires coming from speedo there is a blue and a white wire wire, connect the blue to NMEA 0183 positive output lead of GPS and connect white to negitive output lead of GPS and set menu of speedo to read GPS ON.

[sandiegosteve]

On the wires coming from speedo there is a blue and a white wire wire, connect the blue to NMEA 0183 positive output lead of GPS and connect white to negitive output lead of GPS and set menu of speedo to read GPS ON.

That is the first thing I did. "GPS" doesn't light up, so is this part of my gauge just bad? Everything else seems to work fine.

I appreciate the response.

[boats.net]

Might try connecting only the speedo to gps and disconnect vhf radio from gps to see if is a signal problem.

[hookemup29]

Another Fuel/Speed / GPS question

SDSteve,
Great question... Ive been having the same problem getting my fuel management meter (FMM) to connect with my Lowrance GPS. Im trying to get GPS speed reading to my FMM from GPS. Did you say that you successfully connected a VHF to your GPS via Lowrance data cables (NMEA0183)? Ive contacted Lowrance several times and what they told me doesnt seem to work. Yamaha says to connect the white wire from gauge to the Lowrance NMEA output (I belive it was yellow wire). I grounded the black wires. Went into the menu, turned on COM1 and tried all the baud rates. Still no love... Any suggestions since you seemed to have gotten further than I have with this. My ultimate goal is to be able to get miles per gallon readings using GPS values instead of the values out of the speedo via pitot tube.
Yamaha says they will connect, Lowrance depending on who you talk to says they are not compatible because Yamaha is 0183, Lowrance uses NMEA2000. Dont think it matters myself since one is a protocol while the other is a network configuration???

Thanks

[sandiegosteve]

SDSteve,
Great question... Ive been having the same problem getting my fuel management meter (FMM) to connect with my Lowrance GPS. Im trying to get GPS speed reading to my FMM from GPS. Did you say that you successfully connected a VHF to your GPS via Lowrance data cables (NMEA0183)? Ive contacted Lowrance several times and what they told me doesnt seem to work. Yamaha says to connect the white wire from gauge to the Lowrance NMEA output (I belive it was yellow wire). I grounded the black wires. Went into the menu, turned on COM1 and tried all the baud rates. Still no love... Any suggestions since you seemed to have gotten further than I have with this. My ultimate goal is to be able to get miles per gallon readings using GPS values instead of the values out of the speedo via pitot tube.
Yamaha says they will connect, Lowrance depending on who you talk to says they are not compatible because Yamaha is 0183, Lowrance uses NMEA2000. Dont think it matters myself since one is a protocol while the other is a network configuration???

Thanks

Yes, my VHF does get the GPS signal; 4800 baud works for the VHF. Lowrance has two settings via software for 0183 (tried those too).

Make sure you use the combo power/data cable for 0183. 2000 is a whole different cable.

Since I can't get the GPS signal to work with the FMM, then it might be a compatibility issue. I tried all sorts of configurations with just the FMM and GPS. The VHF works well when I reconnect it...


I was hoping to get a simple answer like the (+) and (-) are backwards, but it looks like something else. Tempting to get a backup GPS that works with it... The pitot does work well when not clogged, and it is actual through water speed.

[hookemup29]

Another Fuel/Speed / GPS question

SDSteve,
Okay well thanks for the update. Sounds like we are both after the same solution which may never work. Does sound like a compatibility issue, I guess Ill just have to go with the pitot speedo instead of GPS. Its too bad the two do not communicate. Let me know if you ever figure out the problem and I will do the same.
Anyone else know the solution to this issue with FMM compatibility with Lowrance GPS via data cable???

Thanks

[boats.net]

I have the same setup on my boat as sandiegosteve but have not connected speedo to GPS only the VHF is connected, I will be out of town for a week but when I get back I will connect it togather and see if I can get an answer for you.

[sandiegosteve]

I just upgraded my Lowrance HDS to the latest version (3.0) and it all works now. Strange, but I guess it was the Lowrance unit's software.

[mdw11771]

Do you splice command into the gps before it goes into the network ??