Forth-eV Wiki

Hier wird eine LED sauber an- und wieder aus geschaltet.

Als Modell diente der Taster, der auch schon in der Demo von tasto und clavis benutzt worden ist. Im Taster ist eine LED integriert. Die soll getoggle werden.

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It's assumed that a program periodically checks whether the switch has been pressed and then changes the state of the LED.

The challenge is to eliminate switch bounce so that the user gets a smooth, reliable impression of the changes. The response should be fast enough to be instantaneous, but slow enough to allow for a safe switchover.

What Pseudo code is.

Function: init ( -- )
  do all initialisation for the intended operation
  set variable ILED, set portpins ...

Function: toggleLED ( -- )  \ toggle LED in a button on and off
  IF: edge detection tells button was pressed 
      toggle LED
      turn off edge detection
  IF: bottom finally has been released
      turn on edge detection

Alternative Implementations

You have another approach to DUMP?

Please add it at the end of this document.