hi gerrit.
the text you type in your post is ascii caracter, with a value from 0 to 255.
The thing you are sending to arduino is TEXT , asci caracters.
here: http://www.asciitable.com/
you can see letter a is decimal value 97
letter s is decimal value 115
this is not the most girly ascii table, but this will surely help you to understand
what you need to understand is that we are sending bytes and values that will be always from 0 to 255.this for arduino, for internet, for anything. its one of the commonest value ( and some how lower), the byte.
when you are looping out of the bounds ( 257 becames 2) its normal. you are in limitation of the type of data. you will loop back.
when i m saying Keyword protocol, it s because the Byte sended to arduino cant exceed value 255.
you are obliged to create your own protocol in VVVV and in arduino to code and decode an information that will be more than 0-255 range.
So for a nice protocol you will create a system of keywords and phrases with values. This will be the encoding in VVVV.
And in arduino you will need to decode this protocol of your own.
If you look about OSC you will surely find sketches and patches that will make it. but i really advice you that it will be a real benefit for you to create from scratch all of that, especially if you plan to work a lot with arduino.
About coding:
you will have a string in VVVV ( a caracter chain), composed of a syntax enabling to see keywords:
for example:
/MYPROTOCOL/MYSLIDERIS/245566/
This string is in fact bytes, shown in letters, each inside bracket is a byte:
[/](/)[M](M)[Y](Y)[P](P).......[5](5)[5](5)[6](6)[6](6)[/](/)
Now shown in values ( decimal), according to the ascii table:
[47](47)[77](77)[89](89)[80](80).......[53](53)[53](53)[54](54)[54](54)[47](47)
So whats there is te real decimal value sended to the arduino.
So, principle is:
transform Strings of keywords and value in a caracter chains. This caracters will be sended to the arduino thruth rs232 node
Now, its where its become tricky, in arduino you will have tp write your own sketch able to decode your data:
You will need a string comparison ( with wstring, included inside the arduino software), to compare and find if your keywords are presents:
The two keywords with slash ( notice we are using slash to begin and close a data)
/MYPROTOCOL/MYSLIDERIS/
then the value, ended by /:
245566/
If your keywords are present and a slash is ending, you can process extraction of you data inside the arduino.
Thats how you can have values biggers than 255, or use float values ( wich are VVVV’s everywhere)
Voilà !