Sending String from Arduino Uno to Using Firmata

Hi every one…
I would like to send string from Uno to .


/* This sketch accepts strings and raw sysex messages and echos them back.
 * This example code is in the public domain.
#include <Firmata.h>

byte analogPin;

void stringCallback(char *myString)

void sysexCallback(byte command, byte argc, byte*argv)
    Serial.print(START_SYSEX, BYTE);
    Serial.print(command, BYTE);
    for(byte i=0; i<argc; i++) {
        Serial.print(argv[i], BYTE);
    Serial.print(END_SYSEX, BYTE);

void setup()
    Firmata.setFirmwareVersion(0, 1);
    Firmata.attach(STRING_DATA, stringCallback);
    Firmata.attach(START_SYSEX, sysexCallback);

void loop()
    while(Firmata.available()) {

And in

Public Class Form1
Private Sub SimpleButton1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SimpleButton1.Click
        FirmataVB1.Connect("COM14", 9600)
            MemoEdit1.Text = (FirmataVB1.SerialPort1.ReadLine).ToString
    End Sub
End Class

When i try to connect… return nothing, only waiting for the responding until error occurs.

Anyone knows how to solve the problem?

did you get ot the bottom of this ?

There are some issues with COM ports 10 and above, with some software. show how to define the name of a port 10 or above. Perhaps this will make a difference.

For those who have problems with Firmata's sysex and want to acess sysex comands easily:

Try - change "storedInputData" variable to public and use it, e.g.:

Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
        arduino1.mycommand1(20, 1)
        Thread.Sleep(100) 'Delay less than a second
        TextBox1.Text = arduino1.storedInputData(1)
End Sub

use and read to add your own sysex command to Arduino.vb