diff --git a/Hardware-installation.md b/Hardware-installation.md
index ab9e275..03792b9 100644
--- a/Hardware-installation.md
+++ b/Hardware-installation.md
@@ -8,3 +8,9 @@ I recommend tapping it from the power switch.
 
 Make sure to measure the pins with a multimeter, so you're not switching around +5V and GND.
 
+Solder a 5-pin female DIN to the MIDI Input and MIDI Output pins.
+The MIDI input needs pins 4 and 5. MIDI Output needs pins 4, 5 and ground. 
+
+All pins are indicated on the board. 
+
+For more advanced features, see the ["Optional features"](https://github.com/sgilissen/purrChestrion/wiki/Optional-features) page here on the wiki.