Small Basic + micro:bit

Ed Price

Former Employee

Feb 13, 2019

First published on MSDN on Sep 13, 2017

Authored by Ed Price

Today is a guest blog post from a teacher, Jez Dean ...

In this blog post : Build a computer-to-micro:bit connection with Small Basic.

Also, see the article from Nonki, Play with micro:bit and Small Basic .

See the article, Small Basic: How to Use micro:bit , for another solution from Nonki that moves the Turtle.

You can write a simple GUI to send commands to a micro:bit running Python:

The program sends Python commands over a serial connection to the micro:bit. I've kept it as simple as possible so you can customize it further.

Clicking PIN0 High sends the command


    pin0.write_digital(1)

to the micro:bit. You could type


    display.show(Image.HAPPY)

and click Send Command would show a smiley on the micro:bit.

Instructions

Flash a Python program to the micro:bit. You can just flash an empty program from within mu.

Install the lit dev extensions for Small Basic. These are used to communicate over a serial connection.

Find out the COM port of your microbit.

Add your COM port at the top of the Small Basic code.

Code


     comPort = "COM4"
     

     

     Initialise()
     

     

     While ("True")
     

     Program.Delay(10)
     

     EndWhile
     

     

     Sub Initialise
     

     'draw window'
     

     GraphicsWindow.Width = 500
     

     GraphicsWindow.Height = 100
     

     GraphicsWindow.Title = "Small Basic Microbit Controller"
     

     

     'draw pin control buttons'
     

     pin0high = Controls.AddButton("PIN0 High", 20, 10)
     

     pin0low = Controls.AddButton("PIN0 Low", 100, 10)
     

     

     'draw status and command buttons & boxes'
     

     statusbox = Controls.AddTextBox(20,50)
     

     value = Controls.AddTextBox(210,13)
     

     send = Controls.AddButton("Send Command", 380, 10)
     

     

     'Open connection to microbit'
     

     Controls.SetTextBoxText(statusbox,"Status : "+ LDCommPort.OpenPort(comPort, 9600))
     

     

     'Assign variables'
     

     Controls.ButtonClicked = OnButtonClicked
     

     nl = Text.GetCharacter(10) 'new line character'
     

     EndSub
     

     

     Sub OnButtonClicked
     

     button = Controls.LastClickedButton
     

     val = Controls.GetTextBoxText(value)
     

     

     'if button pressed, send command and new line character'
     

     If (button = pin0high) Then
     

     LDCommPort.TXString("pin0.write_digital(1)+nl")
     

     ElseIf (button = pin0low) Then
     

     LDCommPort.TXString("pin0.write_digital(0)+n1")
     

     EndIf
     

     If (button = send) And (val <> "") Then
     

     LDCommPort.TXString(val+nl)
     

     EndIf
     

     EndSub