Appendix 

#include <stdint.h>
#include <stdbool.h>

// Actuator Pins
#define MOTOR_FWD_PIN 8
#define MOTOR_BWD_PIN 9
#define MOTOR_ENA_PIN 10

typedef struct ActuatorOut {
uint8_t fwd_pin;
uint8_t bwd_pin;
uint8_t ena_pin;
} AcuatorOut;

const ActuatorOut MOTOR_PINS = {MOTOR_FWD_PIN, MOTOR_BWD_PIN, MOTOR_ENA_PIN};

#define POTENTIOMETER_PIN A5
//------------ActuatorInit-----------
// Function to initialize the direction and enable pins of an actuator.
// Inputs: actuator struct representing actuator configuration
// Outputs: none
void ActuatorInit(const ActuatorOut *actuator) {
pinMode((*actuator).fwd_pin, OUTPUT);
pinMode((*actuator).bwd_pin, OUTPUT);
pinMode((*actuator).ena_pin, OUTPUT);
}

//------------ClipValue-----------
// Function to bound values between two limits. If value is higher/lower than a limit, it is set to that limit.
// Inputs: *val pointer to current value
// upper_lim upper limit for value
// lower_lim lower limit for value
// Outputs: none
void ClipValue(int16_t *val, int16_t lower_lim, int16_t upper_lim) {
(*val) = (*val > upper_lim) ? upper_lim : *val;
(*val) = (*val < lower_lim) ? lower_lim : *val;
}

//------------SetActuator-----------
// Function to set the direction and magnitude of an actuator. Negative magnitude implies
// Counter-Clockwise rotation for a motor and opposing polarity for an electromagnet
// Inputs: mag magnitude of actuator effort between -255 and 255
// actuator struct representing actuator configuration
// Outputs: none
void SetActuator(int16_t mag, const ActuatorOut *actuator) {
// Clip to 8-bit value
ClipValue(&mag, -255, 255);

if (mag > 0) { // Forward Direction
digitalWrite((*actuator).bwd_pin, LOW);
digitalWrite((*actuator).fwd_pin, HIGH);
}
else if (mag < 0) { // Backward Direction
digitalWrite((*actuator).fwd_pin, LOW);
digitalWrite((*actuator).bwd_pin, HIGH);
}
else { // Zero Magnitude
digitalWrite((*actuator).fwd_pin, LOW);
digitalWrite((*actuator).bwd_pin, LOW);
}

// Send actuator command
analogWrite((*actuator).ena_pin, abs(mag));
}

void setup() {
ActuatorInit(&MOTOR_PINS);

}

void loop() {
SetActuator((analogRead(POTENTIOMETER_PIN) - 512)/2, &MOTOR_PINS);

}

HAND WRITTEN WORK