can anyone here tell me if there is a specific boud rate for the Cerbo USB 0 port (the first one to the left) for it to communicate with Arduino Nano though Node Red?
I had it working at one point but something was changed in the settings (or maybe not) and it stopped responding although it shows connected.
The same setup works fine on Node Red on my Mac using 9600 Boud so I’m debating weather Node Red on Venus is causing the problem maybe due to an internal issue?
I am using dev/tty/USB0 as port and 9600 boud rate
When I test the incoming signal from Arduino it sometime comes scrambled and / or at erratic timing.
I have tried different boud rate obviously both in the sketch as well as in Node-Red with no success.
I am quite sure that the device line should read /dev/ttyUSB0. If you have more USB devices connected, that could be /dev/ttyUSB1 as well. In order to get that more stable, you should use something like /dev/serial/by-id/usb-1a86_USB2.0-Serial-if00-port0 (of course that is different on your system). By ssh-ing into you GX, you can determine the correct name. The sequence numbers of the serial devices are given out on discovery, not based on the usb port the device is connected to.
The baud rate is determined by the device attached, not by the GX. So the 9600 baud is correct.
Thanks,
I still don’t understand why it worked fine at first but now only the “Node In” node shows connected and not the Node Out.
I have several Arduino Nano and they all work fine when I test them on my MAC installed Node-Red but no longer in Venus Node-Red.
I have tried different things to analyse the issue,
@Logic28 i am also having this same issue, regardless of if i use serial or modbus ( sketches for both) the timings and scrambled data a erratic at best.
did you manage to find a solution?
Not yet due to other problems caused by all attempts to get USB 0 to work with Arduino as it did the first time.
I might revert to MQTT which works seamlessly on my hot water tank, however, one day i will go back to discover what this problem was.
I might have to reload a fresh version of Venus (not just an update) which is painful as I’ll loos all my settings.
im having to go down the ethernet route i think, or wifi, but i need to also have the 4g LTE working, which seems another battle in its own right when using modbus over ethernet.
I wasn’t even contemplating using WiFi as yet, all my equipment is directly connected via physical link by ethernet so there is no excuse for it not to work; however, this was suppose to create some local digital outputs hence the direct USB connection for simplicity.
As I said, it worked with the first Arduino nano generation, for some reason it did not with a later model but, when I went back to the old one, that didn’t work anymore.
I had been following some advise and worked on Venus in SSH mode so perhaps something was disturbed then
As I said, i much prefer to use MQTT which seems to work seamlessly but at some point I’ll want to know what happened.
i have tried with the UNO and MEGA boards, wat I’ve found is using the serial node in node red give the same type of issue you are having, when i setup the mega as a slave device, and poll it in node red, it is very erratic, drops in and out, but when the data is received , its clean at least.
i have also tried doing some work on SSH to no avai, seems like the venus system keeps disconnecting and reconnecting the RS485 cable, even done some work on FDTI FT prog but this didnt change anything.
i need the gsm to work as this solution is where there is no internet available, annoying how the cerbo drops the GX LTE when ethernet is connected for modbus.
hoping wifi over the cerbo AP will solve this
Hey all, to work with a serial port in Venus OS, also when doing that in Node-RED, you need to “down the serial-starter”, or make that ignore that port.
Thank you Matthijs,
I have got an extremely stable Modbus connection using the Cerbo AP Wi-Fi Connection with an Arduino ESP32 Dev Board. working very well on this. Polling data perfectly with no drop outs.
But i will also try this serial starter fix as well on another project for the USB side, would be very useful to get the USB stable as well
