add note on edbg

README.md

@@ -117,4 +117,8 @@ Those are pretty rough notes, but I can testify that this works well on a window
 
 [Platformio](https://platformio.org/) is a great tool that I've been using to write all of my embedded code lately. It's an extension for [VSCode](https://code.visualstudio.com/), which is essentially Microsoft's fork of [atom](https://atom.io/) (in case you're interested). 
 
-Using CMSIS-DAP for a platformio project is [supported](https://docs.platformio.org/en/latest/plus/debug-tools/cmsis-dap.html), but I still need to figure out how to set it up for use on a custom board... this is on the way. 
\ No newline at end of file
+Using CMSIS-DAP for a platformio project is [supported](https://docs.platformio.org/en/latest/plus/debug-tools/cmsis-dap.html), but I still need to figure out how to set it up for use on a custom board... this is on the way. 
+
+## 4c: Programming with EDBG
+
+[edbg](https://github.com/ataradov/edbg) is a simple command-line programming tool to flash binaries using a CMSIS-DAP programmer. 

samd21-example/samd21-barebones/eagle.epf

 [Eagle]
-Version="09 06 00"
\ No newline at end of file
+Version="09 06 00"
+Platform="Windows"
+Globals="Globals"
+Desktop="Desktop"
+
+[Globals]
+AutoSaveProject=1
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/comm.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/connector.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/dfet.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/fablab.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/lights.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/microcontrollers.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/motors.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/passives.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/power.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/raspberrypi_bastelstube_v13.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/sensor.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/supply1.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/tag-connect-2030.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/tag-connect-2050.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/usbraw.lbr"
+UsedLibrary="C:/Dropbox/CBA/circuits/eagle/parts/SparkFun-Eagle-Libraries/SparkFun-Connectors.lbr"
+
+[Win_1]
+Type="Library Editor"
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+PinDirection=3
+PinFunction=0
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+PinVisible=3
+SwapLevel=0
+ArcDirection=0
+AddLevel=2
+PadsSameType=0
+Layer=94
+Symbol="ATSAMD21E18A-AF"
+
+[Win_2]
+Type="Board Editor"
+Number=3
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+WireBend=1
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+PinFunction=0
+PinLength=2
+PinVisible=3
+SwapLevel=0
+ArcDirection=0
+AddLevel=2
+PadsSameType=0
+Layer=1
+
+[Win_3]
+Type="Schematic Editor"
+Number=1
+File="samd21-barebones.sch"
+View="11.5102 -14.8524 192.551 117.759"
+WireWidths=" 0.0762 0.1016 0.127 0.15 0.2 0.2032 0.254 0.3048 0.4064 0.508 0.6096 0.8128 1.016 1.27 2.54 0.1524"
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+PadDrills=" 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.65 0.7 0.75 0.8 0.85 0.9 1 0.6"
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+ViaDrills=" 0.2 0.25 0.3 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 1 0.35"
+HoleDrills=" 0.2 0.25 0.3 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 1 0.35"
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+DimensionExtOffsets=" 1.27 2.54 1 2 3 0"
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+AddLevel=2
+PadsSameType=0
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+Views=" 1: 11.5102 -14.8524 192.551 117.759"
+Sheet="1"
+
+[Win_4]
+Type="Control Panel"
+Number=0
+
+[Desktop]
+Screen="1920 1080"
+Window="Win_1"
+Window="Win_2"
+Window="Win_3"
+Window="Win_4"