that's actually pretty simple.....

a timer running at 20hz (20 times a second it runs a command). the command checks to see if the reading from a pressure sensor goes above the specified value. if it goes over the value, it turns on a fusion brain output that turns on the wastegate actuator solenoid, allowing boost pressure to hit the wastegate actuator, opening the wastegate, allowing exhaust gas to go around the turbo instead of through it, thus preventing overboost. if the pressure doesn't meet the specified value, it does nothing and keeps the wastegate closed.

most pcm boost control systems use PWM to determine the amount the wastegate opens, but since RRFusion doesn't support PWM, all i can do is a 20hz timer...