Step 8: Microcontrollers and Circuit
The game board is controlled by a PIC (Microchip) microcontroller PIC16F877. The grab tongs have (salad tongs) have a flexible wire attached that is connected to 5VDC. When the grab tongs comes in contact with one of the aluminum sides of any object pickup boxes it will produce a High (5Vdc) bit that is read by the microcontroller and will run a faction for that object. The microcontroller code is in a loop comparing the bits in PortB for a high (5vdc) signal to any of the object pickup area. The code is written when a high (5vdc) signal is detected it will call the box functions for that object pick-up area detected. The box functions will turn on the flashing nose light PortA (Bit0) and PortE (Bit0) buzzer, then it will flash the colored three LED's in that detected box area and then at the end for the function we turn off (clear all inputs and outputs) and the game is ready to play again. This box function will take 3 to 4 seconds to complete and then the game is ready again.
The buzzer (PortA Bit0) is using the TI DRV101 solenoid IC driver that turns on with a high bit on pin1 and the voltage is adjusted by the 10K ohm trim pot connected to pin3. The flashing nose LED (PortE Bit0) is controlled by a high bit on pin4 tunes on the 555 Timer IC and makes the LED flash with the use of the OnSemi power MOSFET MTP10N10EL to increase the current to make the LED's bright. The buzzer is from Radio Shack part #273-55 that runs of 12VDC. The buzzer is mounted on the top positioned toward the players.
The microcontroller will flash the LED's on the detected box by the output in PortD by the Power MOSFET to increase the current to flash the LED's.