Arduino + Visual Basic

[HarryA]

You can use the serial commucations control in VB (Visual Basic) to commucate with an Arduino board. This allows one to make a more formal interface to the board.

The serial comm control is found in project/component/Microsoft Comm Control 6.0 in the VB visual studio. Selecting it adds it to the tool box. It can then be dragged on to the form. Its symbol looks like a telephone.

In this example an Arduino board is controlling an electric motor via an H bridge circuit. The inputs to the bridge circuit are from pins 4, 5, 6, and 7 from the Arduino board.

In the VB code below, the serial interface is setup on loading the form. And four buttons are added: forward, reverse, stop, and exit.

On selecting a button it sends a signal to the board which in turn outputs signals to pairs of pins to the transistors in the H bridge. A more practical interface would have code to ask the user which comm port to connect with.

' VB 6 -motor control via Arduino UNO/Mega 2560

Private Sub Form_Load()
 MSComm1.RThreshold = 3
 MSComm1.Settings = "9600,n,8,1"
 MSComm1.CommPort = 6    'use the one IDE uses
 MSComm1.PortOpen = True
 MSComm1.DTREnable = False
 Text1.Text = ""
End Sub

Private Sub FORWARD_Click()
 Text1.Text = "FORARD DIRECTION WAS SELECTED"
 MSComm1.Output = "f"
End Sub

Private Sub REVERSE_Click()
 Text1.Text = "REVERSE DIRECTION WAS SELECTED"
 MSComm1.Output = "r"
End Sub

Private Sub STOP_Click()
 Text1.Text = "STOP WAS SELECTED"
 MSComm1.Output = "s"
End Sub

Private Sub EXIT_Click()
 MSComm1.Output = "s" 'make sure motor is stopped
 Unload Me
End Sub

On the board side the Arduino code waits for a serial signal then sets or clears the outputs as required.

//this program receives commands via the visual basic program running on the pc
//based on: Patel, Ujash.: "Arduino + Visual Basic 6.0:Make your own software to control Arduino Robot 

//outputs to the four transistors in the 
// H bridge controling the motor
int pin7 = 7;  
int pin6 = 6; 
int pin5 = 5;  
int pin4 = 4;  

void setup() 
{ 
  Serial.begin(9600); 
  pinMode(pin7, OUTPUT); 
  pinMode(pin6, OUTPUT);  
  pinMode(pin5, OUTPUT); 
  pinMode(pin4, OUTPUT); 

  //all low/off = stopped
  digitalWrite(pin4,LOW);  
  digitalWrite(pin5,LOW);  
  digitalWrite(pin6,LOW);  
  digitalWrite(pin7,LOW); 
} 

void loop() 
{ 
  if (Serial.available()) 
  { 
      int command = Serial.read();  
      //all low/off = stopped
      digitalWrite(pin4,LOW);  
      digitalWrite(pin5,LOW);  
      digitalWrite(pin6,LOW);  
      digitalWrite(pin7,LOW); 
      
    if (command=='f') //forward
    { 
      digitalWrite(pin7,HIGH);  
      digitalWrite(pin4,HIGH);  
    } 
     if(command=='r')  //reverse
    {  
      digitalWrite(pin5,HIGH);
      digitalWrite(pin6,HIGH); 
    }
    //we initialize to stop with all LOWs above
    if(command=='s') command = 's'; //dummy statement
    
  }//end if(serial)
}//end Loop()

This project is based on Ujash Patel's book:
"Arduino + Visual Basic 6.0: Make your own software to control Arduino Robot" . Amazon.com Kindle Edition.