diff --git a/readme.md b/readme.md
index 90e3d67..42d5932 100644
--- a/readme.md
+++ b/readme.md
@@ -27,3 +27,8 @@ that loggs data sent by the Arduino via serial interface.
  - data serving python app based on cherrypy
  - UI based on bootstrap3
  - graphing by Dygraphs.js
+
+## Hardware used:
+Arduino mini pro 3.3V
+RaspberryPi (any version basically)
+some wiring together (todo: picture of wiring in svg)