Hi torriem,
Just wondering if you can give me some more info on the firmware version you use and the configuration file.
I have reflow soldered a SX Pro to an adapter board but cant get the config right
XBP9X-DMUS-021
Many thanks,
This should be in its own topic. I’m using the XTC Hopping Firmware (North America), version 2006. There’s also an Australian version, which is version 2206. Config is just a matter of setting Network ID, Preamble ID, Serial port settings. Everything else was left at default. I assume you have the XCTU software working?
Thanks for getting back to me,
Ive had no problems using XCTU but I never changed the firmware so thats were I went wrong 
I ended up making a reflow oven out of a toaster oven and reflowed it to this adpater board;
https://www.ebay.com.au/itm/XBee-868-SMD-to-DIP-adapter-Board-/332724410995
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Very nice!
Hey! I was offered to use a new module “PX1172RH-EVB: PX1172RH EVALUATION BOARD”, cost $ 360. will this work with AOG?
It should, and others have worked on it Dual GPS using SkyTraQ receivers.
I have a working system based on this, however have issues with losing RTK. This appears to be an issue with suspected temperature compensation as you can blow on the receiver and it will lose fix. I also have a system with a F9P and it is rock solid. No troubles with it at all.
Another minor thing is it takes the corrections on one usb and outputs the position on another so I haven’t been able to use the NTRIP through AOG as you can with an Ardusimple board for example.
<Edit: this seems to have been updated so can use just one usb. I will need to update my firmware and try this…>
Did you ever finish your project ?
I did. I have 3 of these units working on local farms. Currently, I have a new revision ordered which will use a different enclosure and PCB design to make a bit more space to install the PCB. I also hope to use the new Dual GPS code which has the integrated NTRIP. My apologies for not having a BOM and PCB design files to release. The local farmers are requesting section control also, and I’m scrambling to get it all done for spring work… Enough said… If I don’t post by midsummer, bump me again as I tend to forget stuff in the scramble they call life. Just in case I didn’t mention this before, I appreciate all the community is doing in the AOG world, and am looking forward to contributing back.
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Here’s a sneak preview of the second revision of the dual GPS system. The enclosure is 6.299" L x 3.543" W (159.99mm x 89.99mm) X 2.362" H (60.00mm)
Sadly, the integrated NTRIP in the dual GPS Esp32 isn’t working yet. I need to try the latest code on mtz8302.
I have made a provision for PWM out on the PCB to connect to rate controllers like TopCon, Raven, and etc.
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Looks nice. The pwm out is the optocoupler on the pcb ? Wish you would tell a little more about how you went about it.
Are you planning to add a W5500 for ethernet ?
Yes, the CNY17 optoisolator is for PWM out. The rate controllers I tested have a 5V output, that gets shorted out with a PWM signal. I believe that’s called sinking. Since I wanted to isolate the grounds (rate controller & dual GPS) anyway, and the Esp32 doesn’t tolerate 5V, an opto was the obvious choice. I am planning on putting in a heavier opto (the cny17 is what I had), even though it’s working fine for the one farmer who requested it.
I added the code to the main dual GPS code from mtz8302 to output PWM per MPH, at the rate selected by the user in the WebUI.
At this time I have no plans to add wired ethernet. I spent a bit of time updating the WiFi code:
- auto reconnect if the WiFi gets lost and comes back again
- upon startup, auto switch between AP and client, whichever happens first. If a user connects to the ESP32 AP, it quits trying to connect to the hotspot. If the hotspot is found, the Esp32 AP is turned off.
This has resulted in a system we are pleased with. I originally wished for a W5500, but WiFi is working so well I doubt I’ll switch, barring future problems. The one concern I had about ethernet is all the cables strung around the tractor. Maybe not really an issue?
For this PCB to be useful, one needs to have my latest code, that I only have locally. Sigh… Maybe by tomorrow I can get the section control off the list, and get some of this code uploaded to Github.
I have been wanting a speed signal for my planter monitor. It is 10v. Could I just bring 12v into a 7810 regulator and use pwm from optocoupler to gnd of 7810 for frequency ?
LM7810
That is another reason I used an optoisolator. It doesn’t matter what voltage you feed into it, as long as it is sinking. Max voltage needs to stay less than 70V of course, as per the datasheet. This means that you can connect / disconnect the wires together really fast, and get a pulse signal on your planter monitor. If you have a 10V signal on your wires, it is very probable that the planter monitor is sourcing. Which means you need a sinking GPS speed output.
If the planter monitor is sinking, you will have no voltage on the wires. Then you hook the 7810 regulator up directly to battery / power source and feed the 10V output through the optoisolator to the planter monitor. If your planter monitor is indeed sinking, could you report back, as I would want to add that feature, configurable with switches or something. There is plenty space on the PCB.
The hookup you described MAY work, but it is non standard. Switching the power to a regulator is typically a bad idea. If you aren’t aware yet, linear voltage regulators usually have capacitors on the input and output, so feeding PWM through the regulator will get lost.
I didn’t think about that, I don’t think it would work. I don’t know of another way to do it short of running through the regulator then through a switch. Any suggestions ?
Ok, I’m a bit confused now. So let’s start at base one. Do you have 10V on the 2 wires on the planter monitor, or did you get the 10V requirement from the monitor manual?
No I don’t believe that would work. Regulators are very slow and aren’t designed to turn on and off quickly.
Instead, attach the 10v to the collector of the optocoupler with a resistor (10k is my go to), and make the emitter ground. Then every time the optocoupler fires, you’ll get a 10v PWM signal. The only catch is it might be opposite to what you need, but that can be dealt with in software on the esp32 side (invert the PWM rate if needed).
Yes I have 10v coming from the planter monitor. I bought a cheap gps speed pulse generator that I am using now, but the frequency is wrong, and the speed shows half.
Okay, 12v to LM7810. 10v ouput to optocoupler collector via 10k resistor. Zero speed is 10v all the time from what I can tell, so pwm to ground should be correct
So you don’t need a 7810 regulator (the planter monitor already has one). The planter monitor sources the current, and the GPS unit sinks the current. The voltage doesn’t matter, as it is less than 70V. @Torriem isn’t wrong, per se, it would only add some more current for the optocoupler to sink. Here’s how it should look:
Obviously the 4N35 has an additional base connection, but just ignore that. The rest is the same.
FYI, the planter monitor has an internal circuit identical to what Torriem described.
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