Dual GPS setups

GPS / RTK / GNSS
405

Thank you for posting an update. It is always nice to know when stuff works. Some days, the satisfaction of getting something working is all one has. :grinning:

I didnā€™t think about any filters, I just found a place in the code that looked like a speed variable that had KMH documented and took it from there.

As far as the speed pulse, my friend called in to a third party GPS receiver speed pulse generator and they got us started down the right track, then we borrowed a local guyā€™s receiver and played with it.

406

Well we have been wanting a speed pulse for those monitors for a long while now, and you got us the parts we needed, so thanks to you and your friend for getting the results.
Thanks for getting me the info on the optocoupler orientation as well. That is what was wrong with my first test.
I can get rid of the hockey puck on my cab now. Every addition just adds to having a simpler and cleaner setup.
There are some on the telegram group that are wanting to output frequency for variable rate and other precision farming additions. Is the output we have from the esp32 able to generate that as well ?

407

Hi, did you have the files for your PCB anywhere? Would be keen to try your dual antenna with 2x Sparkfun boards. Thanks

408

Here is a link to the PCB site I order from AgOpenGPS / Dual GPS PCB w/ NTRIP by Reuben on AISLER. Click on the left top download arrow to get a file you can open in Fritzing. Version 1 is smaller and uses a different enclosure versus version 2. Version 2 has a nicer plug. Click on the right top Revision dropdown for Version 1. Use version 1 at your own risk, as the voltage regulator needs to be substituted with a switching regulator. The F9P config files are in the wild on a flashdrive around here somewhere. You would think I could find a half day to put this on Githubā€¦ I know youā€™re tired of waiting on me, but I need to order some more of these, and I wish to fix some stuff yetā€¦

3 Likes
410

I have been using the code you sent to me for speed pulse output in Matthias esp dual code. I switched to Franz due to some rtk problems and have been trying to put the speed pulse code back in it. Franz code is a bit different than Matthiasā€™ , and I havenā€™t been able to get the code to verify.
Would you mind having a look at Franz code and see if you can get it to work ?

411

It appears to me the speed is in Dualheading/NMEA_Parser.ino at bc843c116579505dedfcf76098143873aea3cd10 Ā· Jeep1945/Dualheading Ā· GitHub

It looks like you need to do a conversion from knots to units of your choice.

So the code to add after that line would look like:

if (millis() - prev_PWM_Millis > 100){
  prev_PWM_Millis = millis();
  double mph_Pwm = float(speeed) * 1.150779; 
  // 1 speeed = 1.852 km/h = 1.150779 mile/h 
  mph_Pwm *= velocityPWM_Multiplier;
  ledcWriteTone(0, mph_Pwm);
}
412

I knew you would have the answer. I did add the code and it compiles. Will test and report back.
Thanks again.
Edit
Got it tested today. Works great. Thanks

413

The schematic wonā€™t load. Is this similar:

Speed pulse

414

Untitled Sketch_schem
Untitled Sketch_schem735Ɨ447 23 KB

Try this one

1 Like
415

Thanks. That looks about the same as long as the monitor has a common ground with the pcb. This will work if the monitor sources the 10V. I donā€™t know if there are other monitors that sink the voltage. Maybe some jumper pins could allow working with either.

416

That is the nice part about a optoisolator, the GND does not have to be the same on the ESP32 and the monitor.

417

If your monitor sinks the voltage (highly unlikely), then you need to know what voltage and how much current draw. Then you would have to use a voltage regulator of the proper voltage and pulse that voltage into the monitor. Again, I think that is highly unlikely, as the commercial GPS speed units donā€™t have that option that I have seen.

418

Probably the monitor source is best. Monitor sink is not needed.

419

I can not flash ESP32. I get an error. Code mtz8302

2022-01-12_01-15-55
2022-01-12_01-15-551920Ɨ1080 186 KB

420

I canā€™t duplicate your problem. Can you post lines 26-39, function EEprom_empty_check() from file zAOG_EEPROM?

421

Is it always the same error?
Go to file - preferences and set compiler-warnings to ā€šnoneā€˜. It may helpā€¦

422

2022-01-12_09-13-43
2022-01-12_09-13-431920Ɨ1080 181 KB
Thank you

423

Thank you. Now I will try to do it.

424

Thank you. Now I will try to do it. Now itā€™s a mistake. zAOG_EEPROM.ino "contains unknown characters.This message appears as soon as you download the file.

425

What board type have you selected? Definitely on the correct one?