Sending text to Arduino via Serial

I´m having a hard time trying to send simple strings from vvvv to an Arduino board.
I want to trigger gadgets connected to the Arduino-board using a simple text.
As the functionality of the Arduino-board will be a bit complex, I cant´t use the Firmata-library and the very comfortable Arduino node from the Addon Pack.
Until now, I CAN get sensor values via strings from the Arduino-board to vvvv, but I want the other way round: Sending strings from vvvv to Arduino-board in order to evaluate the string there. But I´m not successful.

I attached a very basic patch, which shall demonstrate my issue. It does not work. Maybe someone has a solution.
I got inspired on
In this example, Processing sends a string via Serial to the Arduino board. The Arduino board evaluates the string and switches the light either on or off.
In my patch, I´m trying to do the same in vvvv.
I want to replace Processing with vvvv.
Can someone help?

Send_Varchars_vvvv.v4p (6.7 kB)

Hi Wurstbrotrest

I have successfully been sending strings from vvvv to Arduino quite often. So it should definitely work fine.

Did you run that code on Arduino and just tried it with the build in ComPort Monitor from the Arduino Software?

If that works the same should work in vvvv. The only thing I can see in your Patch is that the Send Pin is not connected(bang, second input pin from the left).

Yes, what Kleinkariert said, just put a change (string) between the switch and the do-send pin of the RS232 node. So you only send data when the string is changed.

Thanks for your advice.
I´m testing the Serial Communication on the built-in Serial Monitor inside the Arduino software.
If this works I will know after I´ll have been putting the change(string) node between the switch and the do-send pin of the RS232 node.
I´ll try it this evening. I´ll keep you up to date.

OK, you rule!
It works exactly as you described.

However (for other readers), you can´t open the Serial monitor in the Arduino software while the RS232 node in vvvv is enabled.
Vice-versa the RS232 node will not work, if the Arduino Serial Monitor is open.
In short: You can´t open the same ComPort twice simultaneously.

I´m attaching the vvvv patch for sending strings - additionally a Processing sketch which does the same -
and an Arduino sketch for receiving the strings and switching an LED on or off.
The Arduino and Processing sketches are adapted from:

Simply upload the Arduino sketch to your Arduino board, put an LED between Pin 13 and Ground, then switch it on or off using vvvv. (3.5 kB)

Ahh yes, I mentioned it so many times that I forgot about the “only one software at a time can talk with the Arduino over the RS232 port”

Glad to see it is working :) Might even end up doing a micro video tutorial with your little example.