add links to parts used, fix issue #1

README.md

@@ -9,3 +9,26 @@
 The wiring is pretty straight-forward. A single wire goes from each button to pins 1,2,3,4 and a common ground connecting everybody.
 
 <img width=400 src="./docs/pedalbox_wiring.png">
+
+
+## Parts
+
+The parts used for MIDIPedalBox:
+
+- 1 - Adafruit Trinket M0
+   - [Buy from Adafruit](https://www.adafruit.com/product/3500)
+   - A [QT Py](https://www.adafruit.com/product/4600) or [Seeed XIAO](http://amzn.com/B08745JBRP?tag=todbotblog-20) will work too, with minor code modifications
+
+- 4 - effects pedal switches
+  - I chose these [generic momentary ones](http://amzn.com/B076V8C3LV?tag=todbotblog-20),
+  but there are many to choose from and most all will work. Be sure to check dimensions to be sure!
+
+or if you want push buttons instead of foot switches,
+
+- 4 - 12 mm momentary buttons
+  - I used [these from All Electronics](https://www.allelectronics.com/item/pb-138/spst-n.o.-pushbutton-red/1.html), but the equivalent are [available from Amazon](http://amzn.com/B07F24Y1TB?tag=todbotblog-20)
+
+If you want to add serial MIDI out, the CAD includes a hole for a panel mount MIDI jack,
+like [this one](http://amzn.com/B01GBT9RC0?tag=todbotblog-20)
+
+_(Note: all Amazon links are affiliate links)_