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@@ -1,3 +1,29 @@
 # ProgramChooser
 
-A library for microPython; it can be compared to an app launcher: just launch any function by usage of two buttons
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+## What's this
+
+A library for microPython; it can be compared to an app launcher: just launch any function by usage of two buttons.
+It was tested on a Raspberry Pi Pico. All other microPython boards are expected to work (maybe the LCD driver (see [here](PCF8574.py)) has to be ported)
+
+
+## Needed peripherals
+
+Needed for proper work are:
+
+- an LCD panel with a PCF8574T backpack
+- two buttons
+
+That's it. Nothing more needed.
+
+| Component         | Pin on component |      Pin on Board |
+| :---------------- | :--------------: | ----------------: |
+| Backpack          |             SDA  |             GPIO0 |
+| Backpack          |             SCL  |             GPIO1 |
+| Backpack          |             VCC  |              VBUS |
+| Backpack          |             GND  |               GND |
+| Button 1          |                1 | GPIO2<sup>1</sup> |
+| Button 1          |                2 |               GND |
+| Button 2          |                1 | GPIO3<sup>1</sup> |
+| Button 2          |                2 |               GND |
+
+> [<sup>1</sup>]: This pin can be specified at initialization of the ProgramChooser, see the [examples](examples) folder.
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