The RetroGun Controller Board V1 was designed for a client who needed to drive the effects on a space gun prop that he was building.
The design needed to:
- Be as small as possible
- Control a plasma ball (5V)
- Run a rumble motor (5V)
- Drive a green laser diode (4V)
- Play a sound at power up and another sound when a trigger is pulled
Actions on power up:
- Play a power up sound
- Power up the plasma ball
Actions on trigger pull:
- Power off the plasma ball
- Fire the laser
- Run the rumble motor
- Play a laser sound
I based the design on the ATmega328P and used N-Channel MOFETs to drive the behavior of the various devices.
To reduce the size of the board (and to save time), I used Adafruit’s MicroSD card breakout board+.
This video shows the behavior of the board:
- Even though the trigger employs ATmega328P’s internal pull-up resistor, I found that was insufficient on the the final board. Most likely due to the proximity of the plasma ball. This causes the event to trigger anytime a person came close to the switch wire. Adding an external, 30K pull-up resistor solved the problem.
- Client is still working on the design for the gun. More pictures to follow!