diff --git a/README.md b/README.md
index 6c7b697..54c5033 100644
--- a/README.md
+++ b/README.md
@@ -18,3 +18,22 @@ Generate a PCB with the following features:
 
 # Software
 * Controllable via USB-UART, simple CMD-control
+
+## Interfaces
+* USB-UART
+* GPIOs
+ * RelayA
+ * RelayB
+ * RelayC
+ * RelayD
+ * FAN-PWM
+ * FAN-IN
+ * https://github.com/0110/EADOGS104LCD4Pi
+    * MOSI
+    * MISO
+    * SCLK
+    * CE0
+    * LCD Backlight
+ * Button (optional)
+
+