Code for a one Button RUN / STOP for the BS1

Comments

• VonSzarvas Posts: 3,278

  2022-12-02 14:44

  Hi @Clovey

  I don't have the hardware setup to try, but would something like this work for you ?

  ' BUTTON.BS2
  ' Connect an active-low circuit to pin P0 of the BS2. When you press the
  ' button, the DEBUG screen will display an asterisk (*). The program, as
  ' shown below, will print an asterisk at the first button press, then
  ' delay approximately one second (200 x 5 ms PAUSE) before auto-repeating
  ' at a rate of approximately 100 ms (5 x 20 ms).  Feel free to modify the
  ' program to see the effects of your changes on the way BUTTON responds.
  
  ' {$STAMP BS2}
  ' {$PBASIC 2.5}
  
  Btn             PIN     0
  
  btnWrk          VAR     Byte
  btnLastState    VAR     Byte
  
  btnLastState = 0
  
  Main:
    ' Try changing the Delay value (255) in BUTTON to see the effect of
    ' its modes: 0 = no delay; 1-254 = varying delays before auto-repeat;
    ' 255 = no auto-repeat (only one action per button press)
    '
    ' The BUTTON instruction will cause the program to branch to
    ' No_Press unless P0 = 0
  
    PAUSE 5
    BUTTON Btn, 0, 200, 20, btnWrk, 0, No_Press
  
    IF btnLastState = 1 THEN
      btnLastState = 0
      DEBUG "RUN"
    ELSE
      btnLastState = 1
      DEBUG "STOP"
    ENDIF
  
  No_Press:
    GOTO Main
  
• JonnyMac Posts: 8,927

  2022-12-02 15:57

  I used to write a hundred or so BS1 programs every year around Halloween for people using the EFX-TEK Prop-1 controller (has nothing to do with the Propeller 1 which was released after the BS1-powered Prop-1). To do what you want reliably, you'll want a debounce and force the button to be released. You could do it in a subroutine like this:

  Check_Button:
    timer = 0
  
  CB_Now:
    IF Trigger = NotPressed THEN CB_Exit 
      PAUSE 5
      timer = timer + 5
      IF timer < 50 THEN CB_Now
  
  CB_Release:
        IF Trigger = Pressed THEN CB_Release      ' force release
        PAUSE 100                                 ' let button clear
        state = state ^ 1                         ' flip state
  
  CB_Exit:
    RETURN
  

  This ensures a good button press and then allows a clean release. In the main body of your code you could do something like this.

  Main:
    GOSUB Check_Button
    BRANCH state, (State_0, State_1)
  
  
  State_0:
    ' code for state 0
    GOTO Main
  
  
  State_1:
    ' code for state 1
    GOTO Main
  

  The attached listing compiles, but I did not connect to a BS1.

  bs1

  bs1

  button_check.bs1

  3K

  button_check.bs1 2.5K