Missing util/crc16.h from ModbusMaster.h

[jedi11csa]

Hello,

I have a Renogy Wanderer 10A Solar Charge Controller, which I'd love to get hooked up to an Xiao ESP32 S3.
Ultimately, I'd like to hook this all up and get Home Assistant integrated too. But for now, I'd like to just see the results you're getting.

What I've done thus far:

• I have downloaded your project code and made a project in my Arduino IDE with it.
• I've then read through the notes, and noted the line (19) address to https://github.com/syvic/ModbusMaster to download that repository code for the ModbusMaster.h file.
• Copied the ModbusMaster.h file from that repository into my project folder.
• Noticed in ModbusMaster.h there's an include file required I can't find anywhere.
• Tried verifying the code, knowing it would fail... which it did.

The issue:
I noticed in ModbusMaster.h code, there's an #include <util/crc16.h> on line 83.
As stated above, I tried verifying the code, but get an Output error, which no surprises, Arduino IDE can't find a file or directory called util/crc16.h

The whole point of this...:
How can I get this util/crc16.h file? It isn't in the https://github.com/syvic/ModbusMaster repository.
Also, within this util/crc16.h file, for those who have it, are there any other includes within the file that I'll need too?

I suppose I could also raise an issue at https://github.com/syvic/ModbusMaster, but I'm assuming that people here have this code running and will have the missing util/crc16.h file I need anyway, hopefully ;)

Wondering if anyone can help me out here with the missing util/crc16.h file please? :)

Kind regards,
Chris

[jedi11csa]

Nevermind.

Did some Google-Fu and found this repo: https://github.com/4-20ma/ModbusMaster
Downloaded the zip file and added it to Arduino Library.
Verified okay.

Crisis averted.

[jedi11csa]

Well, I tried with the ModbusMaster stated above. I get an output on the serial monitor, but I get the 0xE2 timeout message.

I assume that by getting this hex value, the code is connecting to the Renogy Wanderer. But, to test things, I changed the slave address to 250, just to see if I'd get the error hex value of 0xE0 (ku8MBInvalidSlaveID) but no...? So, is the address wrong, or right? I would have thought I'd get something saying the address was wrong.

So I tried installing the original ModbusMaster repo syvic, as suggested in the code. Again, I got the missing util/crc16.h error. So, I copied the folder and crc16.h file from the 4-20ma repo into the syvic folder. And... all sorts of errors trying to verify. (Sigh)

I don't know what to do. I need help, but, I fear the author here has sold the whole thing to a faceless corporate entity who doesn't care, and I'll not get that help... unless, they do see this and chime in (nudge-nudge).

Anyway, I still would like this all to work. But, at this point, after emailing the author, posting this issue-string, I doubt it :(

[wrybread]

I haven't sold the repo or anything like that, I just don't have a theory on how to help you. Maybe post to the Arduino forum?

I will say that I didn't have to jump through any of these hoops to get it to compile. But it's been awhile, I don't remember, but I would have made a note if I did.

Please post the solution when you find it.

[SatSearching]

Try installing Modbus Master correctly via Library Manager, remove what you did first.

Same as wrybread above, I didn't have to jump through hoops or manually download and add files, just did what was required via Library Manager.

Why on earth do you think wrybread sold off? His solution totally works and he shared it, I did some changes and in good faith also shared, not sure if you understand MIT and GPL licences? Again, my alterations is credit to wrybread for the original work that works..!

Anyway, to try and help, also make sure your Renogy is RS232, SOME newer versions have switched to RS485, see my repo (based on wrybread) where I have added RS485 support. Also I added circuit diagrams so you can check your connections.

Video below when I was testing, but this was mainly for RS485, may give some clues, address 255 was correct for me.

https://www.youtube.com/watch?v=rN3jovfspVc

Picture below of modbus master installed correctly via Library Manager.

[jedi11csa]

@wrybread Glad to know you're still the owner, and not a faceless corporation 😁
@SatSearching Thank you for your reply! The video is heartening, but I do have RS232 on the Wanderer. Mine is the same as the one pictured in the README. I also removed all the libraries and installed Doc Walkers' ModbusMaster. Thankfully, it does compile now with that library 👍

Unfortunately, I still get both timeout error messages.

I have tried a few different things with the Seeed Xiao ESP32 S3:

• Defining the TX and RX pins a few different ways; On the Xiao, TX is D6 or GPIO43, and RX is D7 or GPIO 44. Have tried 6 and 7, D6 and D7, 43 and 44. But nothing works to resolve the timeout.
• I also tried having two stop-bits "SERIAL_8N2" in "Serial2.begin(9600, SERIAL_8N1, RXD2, TXD2);", again no luck with the timeout issue.

I have the same wiring as in the 'wiring diagram'. In the next few days I'll be able to try out a few more things to test if the RS232 to TTL is the issue.

But my question is, if I am getting a timeout issue (and knowing this as I added in some code to print out the error value to the serial monitor and always getting "ku8MBResponseTimedOut = 0xE2"), can I assume that the slave address is correct? Being 255. I want to rule out that this isn't a factor. I did try changing the address to 1, and 250 another time too, but just got the timeout error. So, there's that...

I do thank both of you for chiming in. Very cool! 🙏❤