Pinter75: Robotics: ExploraBot

Overview
This board is very easy to make, and gives you 12 servo channels, that can support gradual positioning.

The servos are held in that position untill asked to move again. This means that you can create bots that use the torque of your servos to hold their position.

The board is interfaced using rs232 @ 38400bps, and can hold "boot up" servo data in the PIC EEPORM memory.

The Board

Code & Circuits
The code for the PIC and circuit design are from http://home.planet.nl/~j_havinga/servo/servo.htm

Here are some code snippets for VB.net 2008

Imports System.IO

Public Class Form1
'Access the serial port
    Dim WithEvents serialPort As New IO.Ports.SerialPort
    
    ' Connect to rs232 on click of btnConnect_Click
    Private Sub btnConnect_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)  Handles btnConnect.Click
	
        If serialPort.IsOpen Then
            serialPort.Close()
        End If
        Try
            With serialPort
                .PortName = 1 'Or the number of your port
                .BaudRate = 38400
                .Parity = IO.Ports.Parity.None
                .DataBits = 8
                .StopBits = IO.Ports.StopBits.One
                ' Important, leave the encoding as default, else you will only get the 127 ascii table!
                .Encoding = System.Text.Encoding.Default
            End With
        Catch ex As Exception
            MsgBox(ex.ToString)
        End Try
    End Sub

' Disconnect rs232 on btnDisconnect
    Private Sub btnDisconnect_Click( _
       ByVal sender As System.Object, _
       ByVal e As System.EventArgs) _
       Handles btnDisconnect.Click
        Try
            serialPort.Close()
        Catch ex As Exception
            MsgBox(ex.ToString)
        End Try
    End Sub
End Class

' To write to a servo use this:

serialPort.Write(Chr(ServoNum) & Chr(0 - 240))

' Servo on pin 6 is 240, and we write 127 to center it, for example, serialPort.Write(Chr(240) & Chr(127))