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RackCtls is a a collection of components with an "Hi-fi system" appearance:


  • TLEDButton a button with a LED.
  • TLEDButtonPanel its matching panel.
  • TScrewPanel a panel with screws in its corners.
  • TLEDDisplay 7-segment LED display for numerical values.
  • TLEDMeter LED bar graph, Vu-meter style.

The download contains the component, an installation package and a demo application, that illustrates the features of the component.


Original author: Simon Reinhardt Lazarus adaptation by: Luca Olivetti


From the source file:

Diese Komponenten sind Public Domain, das Urheberrecht liegt aber beim Autor.


These components are Public Domain, the copyright however remains with the author. )


The latest stable release can be found here or on Lazarus CCR.

The source repository is here.

Change Log

  • Version 1.20.4 TLEDDisplay can show numbers in hex, use FPC resources for the icons
  • Version 1.20.3 Fix memory leak in TLedDisplay, remove ctl3d/parentctl3d properties (removed from lazarus)
  • Version 1.20.2 Fixed default color for TLedButtn/TLedButtonPanel
  • Version 1.20 Initial release

Dependencies / System Requirements

  • None that I know of

Status: Stable (I hope)


  • The original TButtonPanel has been renamed to TLedButtonPanel since Lazarus has already a TButtonPanel in its standard components palette
  • The license is unclear to me


  • Unzip the file
  • Open the package RackCtlsPkg.lpk in the lazarus ide
  • Click install

The RackCtls Example Application

The sample application is in the LazDemo subdirectory

  • Open RackDemo.lpi
  • compile
  • run