It’s been a while since i did some work on AgOpenGps, now a new major version (4.x) is out. A nice opportunity for a new controller came up as well. Although i like tinkering this time i ordered a pre-assembled dinrail board instead of building my own.
While waiting it for it to arrive, i already had a go at a first overview drawing. Now i would like your thought and suggestions on this implementation. The drawing is full option but a basic setup would be the controller, a grove connector to the ADS_1115/WAS and a motor drive to some gpio pins(almost solder-less)
Some questions to all and especially to @MTZ8302 who wrote most of the esp code.
1 Would the suggested pinout on J14 work?
2 Could the autosteer software be combined with the GPS software (both in one controller)?
3 Is there an accuracy difference in the ads running at 3.3V instead of 5?
4 is the max input voltage in differential mode -3.3~3.3V or would -12~12V also work?
5 Could the network be setup to receive machine PGN on Autosteer over wifi and forward them to ethernet connected machine controller on the implement?
6 I have a bunch Ublox M8T’s can these be forwarded to rtklib/navi>AOG of just use them as base?
7 Would anyone use this controller with the GSM / Lora option for RTK (and is it even possible)?
8 Your questions/suggestions or things i forgot?
I relay like the idea of using the pre build ESP32 system.
For the ads, look into the datasheet, I’m using it with level shifter to have 5v at the ads to be able to read the Fendt’s WAS with 4,8v max. The incoming voltage must be less than Vin.
The pins I33 and I34 are input only and don’t have internal pull ups. I have never used them for serial, you just ahve to try. Used for switch detection high/low with external pullups they work perfectly.
The forwarding of the data from Wi-Fi to Ethernet might work, but needs to be coded. Alternatively use a Wi-Fi router with Ethernet connection to link it with an other router at the tablet, or place it to the autosteer and connect the tablet via WIFI.
With lora I don’t have any experience, as I use NTRIP via GSM.
I like tinkering but this was a no brainer indeed, and anyone can order one or even two for about the price of PCB V2 without assembly.
Already had a look at that datasheet and also thought about using a level-shifter just was wondering if one got a better signal less noise at 5v resolution will still be the same. So am i right here: it is only half resolution when using 0~5V in differential mode over full when using -5~+5V.?
Using RS485 would be even better for noise, only thing uart0=programming/usb uart1/2 is gps meaning it would have to be on a softserial instead.
Still waiting for the hardware first ESP32 here, been used to the 8266.
Know pins I33 and I34 are input only, but the LORA/GSM modules seem to use them as well.
The router/switch i like as an option when running more devices on the implement (section,rate,tree) but is also a extra piece off hardware not needed in a basic setup.
Guess in europe most of us will use GSM with NTRIP, same here. The lora thing would be in more rural areas without good coverage. So i don’t use them either, thing is if someone wants i should keep the pins free or they should use lora on their reciever.
There are some things still to be implemented for this so if it can be usefull for other users we could account for that. Just need the idea’s what that should be.
IF you used a simple resistor divider to lower the WAS volatge, could you just use the ESP A/D ?
If 12 bit would be sufficient sure could do that.
Only drawed it like this because there is no input portection on the direct pins. wrong voltage goodbye esp32 was hoping the ads1115 also gave some extra protection, not as bad pricewise to replace.