Delphi/Lazarus - API Bindings

The Delphi/Lazarus bindings allow you to control Bricks and Bricklets from your Delphi/Lazarus programs. The ZIP file for the bindings contains:

  • in source/ the source code of the bindings
  • in examples/ the examples for every Brick and Bricklet


  • Delphi 2007 or newer, or Lazarus (Free Pascal Compiler 2.4 or newer), other Delphi or Object Pascal compilers might work as well


To keep the Delphi/Lazarus bindings stupid and simple, they only have dependencies that are available nearly everywhere, thus making it possible to compile into any project hassle-free. We do not offer a precompiled library, since it would be a pain in the ass to provide them for all combinations of architectures and operating systems. This means, the bindings should work on most architectures (ARM, x86, etc.) and on most operating systems (Windows and POSIX systems such as Linux and Mac OS X, etc.).

Because there is no precompiled library for the Delphi/Lazarus bindings there is nothing to install as such. The recommended way of using the bindings is to include their source code directly into your Delphi/Lazarus project. The next section shows some examples about how to do that.

Testing an Example

To test a Delphi/Lazarus example Brick Daemon and Brick Viewer have to be installed first. Brick Daemon acts as a proxy between the USB interface of the Bricks and the API bindings. Brick Viewer connects to Brick Daemon and helps to figure out basic information about the connected Bricks and Bricklets.

As an example we will compile the Stepper Brick configuration example with the Free Pascal Compiler (FPC), as well as the Lazarus IDE and the Delphi IDE. For that we have to copy the IP Connection and the Stepper Brick bindings from the source/ folder as well as the ExampleConfiguration.pas from the examples/Brick/Stepper/ folder into a new folder:

 -> Base58.pas
 -> BlockingQueue.pas
 -> BrickDaemon.pas
 -> Device.pas
 -> DeviceBase.pas
 -> IPConnection.pas
 -> LEConverter.pas
 -> SHAone.pas
 -> TimedSemaphore.pas
 -> BrickStepper.pas
 -> ExampleConfiguration.pas

In the example HOST and PORT specify at which network address the Stepper Brick can be found. If it is connected locally to USB then localhost and 4223 is correct. The UID value has to be changed to the UID of the connected Stepper Brick, which you can figure out using Brick Viewer:

  HOST = 'localhost';
  PORT = 4223;
  UID = 'XYZ'; { Change to your UID }

Free Pascal Compiler (FPC)

FPC automatically finds the used units, therefore a compilation of the project with FPC looks like this:

fpc ExampleConfiguration.pas

Runtime Error 211

If you get Runtime Error 211 on starting your program or it prints:

Threading has been used before cthreads was inizialized.

Then you need to add CThreads to the front of your Uses list of your program.

Lazarus IDE

With Lazarus we can use our example_project/ folder by clicking:

  • Project
  • New Project from file ...
  • Choose example_project/ExampleConfiguration.pas
  • Click Open
  • Choose "Console Application"
  • Click OK
  • Choose "Application Class Name" and "Title"
  • Click OK

That's it, now the project can be compiled an executed!

Runtime Error 211

If you get Runtime Error 211 on starting your program or it prints:

Threading has been used before cthreads was initialized.

Then you need to add -dUseCThreads to the Lazarus compiler options at:

  • Project
  • Project Options ...
  • Compiler Options
  • Other

Then recompile the project. If that does not fix the problem then you need to add CThreads to the front of your Uses list of your program.

Delphi IDE

With Delphi XE2 (older Delphi version should work similar) we can use our example_project/ as follows. First rename ExampleConfiguration.pas to ExampleConfiguration.dpr then click:

  • Project
  • Add Existing Project...
  • Choose example_project/ExampleConfiguration.dpr
  • Click Open

That's it, now the project can be compiled an executed!

API Reference and Examples

Links to the API reference for the IP Connection, Bricks and Bricklets as well as the examples from the ZIP file of the bindings are listed in the following table. Further project descriptions can be found in the Starter Kits section.

  API Examples
IP Connection API Examples
DC API Examples
IMU API Examples
IMU 2.0 API Examples
Master API Examples
RED API Examples
Servo API Examples
Stepper API Examples
Accelerometer API Examples
Ambient Light API Examples
Ambient Light 2.0 API Examples
Analog In API Examples
Analog In 2.0 API Examples
Analog Out API Examples
Analog Out 2.0 API Examples
Barometer API Examples
CAN API Examples
CO2 API Examples
Color API Examples
Current12 API Examples
Current25 API Examples
Distance IR API Examples
Distance US API Examples
Dual Button API Examples
Dual Relay API Examples
Dust Detector API Examples
GPS API Examples
Hall Effect API Examples
Humidity API Examples
Industrial Analog Out API Examples
Industrial Digital In 4 API Examples
Industrial Digital Out 4 API Examples
Industrial Dual 0-20mA API Examples
Industrial Dual Analog In API Examples
Industrial Quad Relay API Examples
IO-16 API Examples
IO-4 API Examples
Joystick API Examples
Laser Range Finder API Examples
LCD 16x2 API Examples
LCD 20x4 API Examples
LED Strip API Examples
Line API Examples
Linear Poti API Examples
Load Cell API Examples
Moisture API Examples
Motion Detector API Examples
Multi Touch API Examples
OLED 128x64 API Examples
OLED 64x48 API Examples
Piezo Buzzer API Examples
Piezo Speaker API Examples
PTC API Examples
Real-Time Clock API Examples
Remote Switch API Examples
RGB LED API Examples
Rotary Encoder API Examples
Rotary Poti API Examples
RS232 API Examples
Segment Display 4x7 API Examples
Solid State Relay API Examples
Sound Intensity API Examples
Temperature API Examples
Temperature IR API Examples
Thermocouple API Examples
Tilt API Examples
UV Light API Examples
Voltage API Examples
Voltage/Current API Examples