VB.NET and Arduino

Forum 2005-2010 (read only) Hardware Interfacing
1

Hello

I would like to send and read data from Arduino Duemilanove.

I've established a connection via mscomm control but it's difficult: "if I send a command...let's say "P5O" arduino reads only one character.
I would like Arduino to read commands and respond to them.

I also tried FirmdataVB with limited success: I could activate a pin to light a LED but not set his value/voltage. I also could not read from analog pins. FirmdataVB looks like the way to go with the protocol, but it's not providing all the basic functions.

Any help would be appreciated

2

VB.NET might be hard, but that doesn't qualify as a reason for posting in the hardware section.

There are plenty of examples for how to read more than a single byte from the serial port. zoomkat and I have both posted ways to do it. A little time with the search field and button would go a long way towards finding you answers.

Note: I am NOT picking on the newbie.

3

sorry, meant to post in software > interfacing

I would prefer using firmdataVB as I don't have to write the protocol myself. But i'm having problems with it as described above.

will check the multy-byte sending out

4

I would prefer using firmdataVB as I don't have to write the protocol myself.

Defining a protocol is easy. Implementing it is not much more challenging. Getting a string of characters sent and read is the hard part, and there are plenty of examples (search for "started && ended", for example).

Parsing the string is pretty easy, too. Some ways of formatting the string are easier than others. "<8:1>" to turn on pin 8 is a bit easier to parse than "Hey, what say you turn pin eight on".

If you get stuck, make a list of the things that the VB app wants the Arduino to do, and post it here.

5

ok, will search for it and try.

Basically I want to control arduino with commands like you mentioned.
something like:

  • turn on pin1 with voltage/value 200: "P1_OUT_200"
  • report value on pin5: "P2_IN"
    ...
6

Here is the code I was referring to:

char inData[24];
byte index;
boolean started = false;
boolean ended = false;

void loop()
{
  while(Serial.available() > 0)
  {
      char aChar = Serial.read();
      if(aChar == '<')
      {
          started = true;
          index = 0;
          inData[index] = '\0';
      }
      else if(aChar == '>')
      {
          ended = true;
      }
      else if(started)
      {
          inData[index] = aChar;
          index++;
          inData[index] = ',';
      }
  }

  if(started && ended)
  {
      // Do something with the data

      // Get ready for the next time
      started = false;
      ended = false;

      index = 0;
      inData[index] = '\0';
  }
}

Basically I want to control arduino with commands like you mentioned.
something like:

  • turn on pin1 with voltage/value 200: "P1_OUT_200"
  • report value on pin5: "P2_IN"

A space between the P and the 1 (or 2) would be good. Spaces make better delimiters than underscores, in my opinion.

7

I'm trying to compile your code and it says: "function main: undefined reference to `setup'" ? sample code compiles ok

8

oh, my bad. forgot to add void setup to the code

9

Nice, got the protocol to work with your loop and strtok loop. Will use your suggested format: <1:2:3:4>

first part: analog od digital pins
second part: pin number
third part: input or output
fourth part: value

Just needed a push in the right direction.

Thank you