MI6
Power
This is the power into the Mi6. A 7.2V nicad battery is run into a LM7805 voltage regulator, which pulls it down to 5 volts. A power switch allows you to turn on and off the MI6. Two bypass capacitors make sure the power is smooth and clean, and an indicator LED in parallel allows you to visually confirm when the switch is closed and power is flowing. This five volts then powers the other MI6 circuitry seen below.
TIVA
This is effectively a visual pin-out diagram. Pins D0 and D1 go to a shift register circuit which controls the 7 segment LEDs (this circuit can be seen below). D3 goes to the Coin/Card slot sensor, and E1 and E2 are the input lines to the joysticks. A6 and A7 are the limit switches we use as shoulder button son the gamepad, while D6 and D7 are the pair/unpair command lines. C4-C7 are the serial communication to the Xbee and Bluetooth.
Joystick, coin sensor and buttons
This is a collection of simple circuits. The joysticks are simply potentiometers, and as we saw above, they are analog inputs directly into the MI6 Tiva. The Coin/Card slot sensor is simply a slot sensor which detects a break in the IR LED -> IR sensor and outputs a digital signal accordingly. And finally, the button circuits are simply buttons which short to ground when pressed. Their input lines are pulled HI using internal circuity on the Tiva.
Communication
The Xbee and Bluetooth circuitry is exceedingly simple; it is within the communication code that the magic happens. One simply connects serial RX and TX lines from the microcomputer to the TX and RX lines on the Xbee, and the Bluetooth respectively. Then, in code, one must correctly communicate with the devices.
Seven segment
The seven segment LED circuitry utilizes a 74HCT595 shift register. This turns one output line into 7, allowing us to control the 7 segment display with just one output (well, 3 since the SCLK, RCLK, and SDI line all need to be controlled, but it still simplifies your circuitry).
These seven segment displays are used to indicate which hovercraft we are paired with, or attempting to pair with.