Driving a Servo

Now is a good time to get something to move with our board by connecting a servo. I directly go to the supplied SoftPWMServo library as it offer to run a servo ono any GPIO pin of the chip. In the example, I connect the servo to the pin 4 on the right side of the board:

The code is quite simple and straight forward:

const uint8_t LEFT=0;
const uint8_t RIGHT=1;
uint8_t nP[2][8] = {{0,17, 9,10,11,12,13,14},{18,17, 1, 2, 3, 6, 7, 8}};

#include <SoftPWMServo.h>

int pos = 0;         // variable to store the servo position, in microseconds
const int pin = nP[RIGHT][3];  // Choose _any_ pin number on your board, i.e. pin 3, right side

void setup()

void loop()
  for(pos = 1000; pos < 2000; pos += 10)  // goes from 1ms to 2ms
  {                                       // in steps of 10us
    SoftPWMServoServoWrite(pin, pos);     // tell servo to go to position in variable 'pos'
    delay(25);                            // waits 25ms for the servo to reach the position

For a specific servo, it is useful to test to extend the range for the position to 500 - 2500 ms. I was surprised by the smoth movement of the servo compared to the normal servo lib I used in the Arduino setup.