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README.md

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+# Radio Board Control Software
+
+Runs on the [Radio PCB (Earl
+Grey)](https://github.com/waterloo-rocketry/canhw/tree/master/radio). This
+board is responsible for all communications between the rocket's
+onboard electronics and the ground support equipment (GSE). It's also
+responsible for the power state of all RocketCAN PCBs, being able to
+disconnect power from the CANbus in order to extend battery life.
+
+Radio board maintains counts for how long it's been since it received
+a heartbeat message from each board on the bus
+([canlib/message_types.h::BOARD_STAT
+message](https://github.com/waterloo-rocketry/canlib/blob/master/message_types.h))
+in order to report other system failures to the GSE.
+
+## How to build and run
+
+- Open MPLAB X
+- Connect a PICKIT 3 to your computer via USB
+- Line up the PICKIT cable such that the red wire lines up with A) the
+  arrow on the PICKIT, and B) the MCLR marking on the board.
+- Power the board through the 12V barrier block. The positive terminal
+  should be indicated with red paint.
+- Click the "Make and Program Device" toolbar button in MPLAB.