added analog sensors and cleaned up the sensor data structure a bit
diff --git a/gyro_board/src/usb/analog.h b/gyro_board/src/usb/analog.h
index 1de38e7..5a06290 100644
--- a/gyro_board/src/usb/analog.h
+++ b/gyro_board/src/usb/analog.h
@@ -3,7 +3,13 @@
#include <stdint.h>
+// Starts the hardware constantly doing conversions on all 4 of our analog
+// inputs.
void analog_init(void);
-int analog(int channel);
+
+// Retrieves the most recent reading on channel (0-3).
+// Returns 0xFFFF for invalid channel.
+// 0 means 0V and 0x3FF means 3.3V.
+uint16_t analog(int channel);
#endif // __ANALOG_H__