Solder Flora Pins
Flora is the low powered microcontroller that will be running the code for this project. Use an exacto knife to cut away 14 male header pins and drop through the mounting holes for the Flora. Seat the Flora onto the pins to hold in place while you solder the bottom of the pins to the board. The USB connector on the FLORA should be at the bottom of the board in this picture. We are not soldering the Flora to the board at this time, just the header pins. It is easier if you have someone hold the Flora against the circuit board while you solder the bottom pins.
Solder the SPDT Relay
A Single Pole Double Throw Relay is used to eliminate outside noise and provide a true High/Low value to the interrupt pin on the Flora. When the interrupt pin state changes, Flora will wake up, turn on the XBee end device radio and send a message to a router or coordinator radio. Flora will also activate a series of NeoPixel lights to illuminate the inside of the mailbox. Solder the 6 pins on the SPDT Relay to the board now.
Solder the Female Header 10 Pins
This header allows for the XBee radio to be easily seated and removed from the board for reprogramming and upgrading at a later time.
Solder the 5 Terminal Screw Headers
The 5 Terminal Screw Headers will be used to connect the outside wires coming into the box to the circuit board. If you are facing the inputs to the terminal screw headers, from left to right, the input pins are for Voltage Output, Photocell Pin, NeoPixel Pin, Door Pin, and Ground.
Top View of Board
Solder the Flora to the male header pins and use wire cutters to trim away the excess pins. This is required so the pins to not touch the solar panel charging board. Also solder the 1K resistor at this time (see photo). The 1K resistor is used in conjunction with the photocell as a pull down resistor.
Prepare the Solar Charger Stands
Cut away 8 male header pins and double stack the black plastic stands on 4 of the pins. These 4 pins will be used to position the solar charger board over top the Flora.
Solder the Solar Charger Pins
This is easier to do with a second pair of hands. Have one person hold the board upside down and hold each pin in place with a pair of needle nose pliers while you solder to the bottom of the board.