This project gives a speed control of DC motor through PWM method. The Dc motor is derived by the L298 driver IC.

You can also control the direction of the motor.

There are three buttons to control the motor. Also a bar graph Led display indicate the speed of the motor.

An proteus simulation file is also available at the download so that you can check the code on your PC.

Circuit Diagram

DC-moto-speed-control

Bascom Code

$regfile = "m16def.dat"
$crystal = 1000000
'============================================================================
Config Timer1 = Pwm , Pwm = 8 , Compare A Pwm = Clear Down , Prescale = 1024
Config Portb = Input
Config Portc = Output
Config Porta = Output
'============================================================================
Dim A As Word , B As Bit
'============================================================================
Declare Sub Progress(num As Word)
'============================================================================
A = 100
Pwm1a = A

Portc.0 = 1
Portc.1 = 0
B = 0
'============================================================================
Do
'////////////////////////////////////////////////////////////////////////////
If Pinb.0 = 1 Then
   A = A + 10
   If A >= 250 Then A = 250
   Pwm1a = A
   Waitms 250
End If
'////////////////////////////////////////////////////////////////////////////
If Pinb.1 = 1 Then
   A = A - 10
   If A <= 10 Then A = 10
   Pwm1a = A
   Waitms 250
End If
'////////////////////////////////////////////////////////////////////////////
If Pinb.2 = 1 Then

   If B = 0 Then
      B = 1
      Portc.0 = 0
      Portc.1 = 1
   Elseif B = 1 Then
      B = 0
      Portc.0 = 1
      Portc.1 = 0
   End If
   Waitms 250

End If
'////////////////////////////////////////////////////////////////////////////
Call Progress(a)
'////////////////////////////////////////////////////////////////////////////
Loop
'============================================================================
End
'/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\

Sub Progress(num As Word)

If Num < 25 Then
   Portc.7 = 1
   Portc.6 = 0
   Porta = 0
End If
If Num < 50 And Num >= 25 Then
   Portc.6 = 1
   Portc.7 = 1
   Porta = 0
End If
If Num < 75 And Num >= 50 Then
   Portc.6 = 1
   Portc.7 = 1
   Porta = &B00000001
End If
If Num < 100 And Num >= 75 Then
   Portc.6 = 1
   Portc.7 = 1
   Porta = &B00000011
End If
If Num < 125 And Num >= 100 Then
   Portc.6 = 1
   Portc.7 = 1
   Porta = &B00000111
End If
If Num < 150 And Num >= 125 Then
   Portc.6 = 1
   Portc.7 = 1
   Porta = &B00001111
End If
If Num < 175 And Num >= 150 Then
   Portc.6 = 1
   Portc.7 = 1
   Porta = &B00011111
End If
If Num < 200 And Num >= 175 Then
   Portc.6 = 1
   Portc.7 = 1
   Porta = &B00111111
End If
If Num < 225 And Num >= 200 Then
   Portc.6 = 1
   Portc.7 = 1
   Porta = &B01111111
End If
If Num < 255 And Num >= 225 Then
   Portc.6 = 1
   Portc.7 = 1
   Porta = &B11111111
End If

End Sub

Download

Bascom code & proteus simulation file