Sorry, I missed that. The link says
2.ENA1 is motor enable port,can connect with PWM to adjust 1# motor speed;ENA2 can regulate speed for 2# motor
3.IN1,IN2 can control 1# motor positive/negative rotate,braking,trigging;IN3,IN4 can control 2# motor
which would require slightly different code. Something like this
byte motorSpeed = 123;
byte motorSpeedPin = 6;
byte motorFwdPin = 7;
byte motorRevPin = 8;
void setup() {
pinMode(motorSpeedPin, OUTPUT);
pinMode(motorFwdPin, OUTPUT);
pinMode(motorRevPin, OUTPUT);
digitalWrite(motorRevPin, 0);
digitalWrite(motorFwdPin, 1);
analogWrite(motorSpeedPin, motorSpeed);
}
void loop() {
}
...R