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Topic: Receiving NMEA 0183 data from fishfinder using data converter (Read 296 times) previous topic - next topic

slr_555

The Lowrance unit has an adjustable baud rate, and I set it to 4800. Yes, I tried all the baud rates, the 4800 seemed to be the best one, all the others were even moreso jibberish. I also tried setting the fishfinder to higher baud rates. Ive messed around with the baud rates a lot and I really don't think that's the problem.

Does this mean the data converter is the problem?

chucktodd

The Lowrance unit has an adjustable baud rate, and I set it to 4800. Yes, I tried all the baud rates, the 4800 seemed to be the best one, all the others were even moreso jibberish. I also tried setting the fishfinder to higher baud rates. Ive messed around with the baud rates a lot and I really don't think that's the problem.

Does this mean the data converter is the problem?
One more thing, is the data Inverted, or have you connected rx+ to tx-?

Converter  |  FishFinder
rx+         -|-   tx+
rx-          -|-   tx-
tx+         -|-   rx+
tx-          -|-   rx-


try setting up
Code: [Select]

SoftwareSerial ss(rxPin,txPin,true);

This will tell Software Serial to use inverted logic levels for TX, RX values.

Chuck.


Check out my Kickstarter Project Memory Panes an expansion RAM Shield for Mega2560's.  It adds 1MB of RAM for those projects where 8KB is not enough.


chucktodd

The Lowrance unit has an adjustable baud rate, and I set it to 4800. Yes, I tried all the baud rates, the 4800 seemed to be the best one, all the others were even moreso jibberish. I also tried setting the fishfinder to higher baud rates. Ive messed around with the baud rates a lot and I really don't think that's the problem.

Does this mean the data converter is the problem?
I think I found your Error.  In then Convert Manual Page 3,  Have you configured your converter for RS422 or are all the jumper configured for RS485?  Attached is a screen grab of the manual image.
Make sure the jumpers are correct.

Remove all of the jumpers except the J4 jumper.  I think your pictures show the jumpers still in place.

Chuck.


Check out my Kickstarter Project Memory Panes an expansion RAM Shield for Mega2560's.  It adds 1MB of RAM for those projects where 8KB is not enough.

jboyton

Does this mean the data converter is the problem?
It could be. Or maybe it's a wiring error. It's easy to get confused about the directions of the different TX and RX pins. Or maybe it's a jumper problem as Chuck is suggesting.

If you think the converter could be bad it's possible to test it without the fish finder by wiring it for a "loopback" test. The idea there is to short TX+ to RX+ and TX- to RX-, provide 5V and GND for power, and then wire the TTL TX to the Arduino TX and the TTL RX to Arduino RX. Then open the serial monitor and anything you type should be echoed back to you. There's plenty of opportunity to wire something wrong just for this test so it's worth double checking the wiring and jumpers first.

What sort of fish are you hoping to catch?

slr_555

Thanks for all your help guys. I'm actually currently working as a fishing guide up at a lodge in northern Ontario. We've had bad weather recently and so the internet has been spotty. I will try your suggestions tonight.

I think I found your Error.  In then Convert Manual Page 3,  Have you configured your converter for RS422 or are all the jumper configured for RS485?  Attached is a screen grab of the manual image.
Make sure the jumpers are correct.

Remove all of the jumpers except the J4 jumper.  I think your pictures show the jumpers still in place.

Chuck.


Check out my Kickstarter Project Memory Panes an expansion RAM Shield for Mega2560's.  It adds 1MB of RAM for those projects where 8KB is not enough.

Where are the jumpers located on the converter here?

I don't see where I can configure that.

jboyton

It's a little hard to see but I think Chuck is right.


slr_555

OH ok, I found it, they were pretty jammed in there and the plastic needed to be broken apart. I'll post results tonight. The next step if this works is having it interface with my data logging shield, and recording the data. Id rather not have to bring my laptop in the boat with me.
 

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