DRV8871 motor driver on an Arduino Uno

// A 12 V motor on an Adafruit DRV8871 breakout, from an Uno.
//
//   DRV8871 IN1 -> pin 9    IN2 -> pin 10    GND -> GND
//   DRV8871 VM / GND terminal -> 12 V,  OUT1 / OUT2 -> the motor
//
// The DRV8871 has no enable and no logic supply. Its table:
//   IN1 high, IN2 low: forward     IN1 low, IN2 high: reverse
//   both low: coast                both high: brake
// So speed is PWM on one input with the other low (drive, then coast).

const int IN1 = 9;
const int IN2 = 10;

void setup() {
  pinMode(IN1, OUTPUT);
  pinMode(IN2, OUTPUT);
  Serial.begin(9600);
  Serial.println("Mokxi Uno: DRV8871 forward, brake, reverse, coast");
}

void loop() {
  Serial.println("forward, speeding up");
  digitalWrite(IN2, LOW);
  for (int s = 0; s <= 255; s += 51) {
    analogWrite(IN1, s);
    delay(300);
  }
  Serial.println("brake");
  digitalWrite(IN1, HIGH);
  digitalWrite(IN2, HIGH);
  delay(1000);
  Serial.println("reverse");
  digitalWrite(IN1, LOW);
  digitalWrite(IN2, HIGH);
  delay(1500);
  Serial.println("coast");
  digitalWrite(IN2, LOW);
  delay(1500);
}