There are two ways to power the board: by , well, powering it up, or by plugging in a PICKIT3 programmer/debugger unit, and powering the board through that. It’s surprisingly convenient to use just the PCIKIT3, especially when you are travelling.
If you are powering by batteries, we find two AA cell batteries in a small two cell battery holder works best during development. The board will run happily from two Alkaline, NiCad or NMiH batteries. No external regulator is required; just connect the batteries directly to the appropriate board pins ( GROUND and 3v3, as shown on the PCB layout drawing.)
Powering via the PICKIT3 is even simpler. Just plug in the PICKIT3 as normal:
Note how the PICKIT3 appears “upside down”. It’s not a problem; the LEDs on the top of the PICKIT3 are not really interesting. Only five of the six header pins are used, starting at pin1 (marked by a triangle on the top of the PICKIT3.)
Plug the PICKIT3 into the PC, and start the MPLAB-X application. Click on the “Hold in Reset” icon, as shown in the figure below.
Once the text in the lower “Output” dialog indicates that the PICKIT3 has connected to your board (“Target Detect”,) click the button again, and the board will power up.
Please note: If you continue to use the board with the bootloader application, you should add a resistor ( a value between 4K7 and 50K) between pin 18, PORTC7, and 3.3V. This ensures that the bootloader does not start when you are running your board without a serial cable connected. This resistor is only required for application that use the serial port (like the bootloader.)