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+# Test firmware
+
+Use this firmware to test all hardware components of a Pentabug. Add a
+`pentatonic` extension and press all buttons. The buttons test the following
+components (from left to right):
+
+* flash LED 1
+* send IR signal; receiving this signal flashes LED 2
+* plays (lower) tone using BUZGND
+* plays (higher) tone using BUZZR
+* starts the vibration motor
+
+This test should catch most obvious errors, but not all possible errors. Some
+pinouts are not tested (e.g. JP3 and some pins of JP4 and JP5).
+