Not declared in scope

Using Arduino Programming Questions
1 
#define POT1_PIN A1
#define POT2_PIN A2

#include <X9C103S.h>
void setup() {
  Serial.begin(9600);
  X9C103S pot1(1, 2, 3);
  X9C103S pot2(4, 5, 6);
  pot1.initializePot();
  pot2.initializePot();
}

void loop() {
  int resistance1 = map(analogRead(POT1_PIN), 0, 1023, 0, 100);
  int resistance2 = map(analogRead(POT2_PIN), 0, 1023, 0, 100);
  pot1.setResistance(resistance1);
  Serial.write("Potentiometer 1:");
  Serial.write(pot1.getResistance());
  pot2.setResistance(resistance2);
  Serial.write("Potentiometer 2:");
  Serial.write(pot2.getResistance());
}
2

I'm trying to make my sons power wheels variable speed. I started with a PWM motor controller and a 3 wire pedal (pot) but its lowest value is too high to stop the motors. I was planning on sticking an arduino in so I can map the real pot to output the value to the digital pot that way I can control the bottom and the top. Any help would be appreciated.

3

Try moving the instantiation outside the loop();

(confusing that the example in the library has it "wrong"... if this works)

** but I think you should not use pin 1 (even as a test pin)

#define POT1_PIN A1
#define POT2_PIN A2

#include <X9C103S.h>
X9C103S pot1(1, 2, 3);
X9C103S pot2(4, 5, 6);

void setup() {
  Serial.begin(9600);
  pot1.initializePot();
  pot2.initializePot();
}

void loop() {
  int resistance1 = map(analogRead(POT1_PIN), 0, 1023, 0, 100);
  int resistance2 = map(analogRead(POT2_PIN), 0, 1023, 0, 100);
  pot1.setResistance(resistance1);
  Serial.write("Potentiometer 1:");
  Serial.write(pot1.getResistance());
  pot2.setResistance(resistance2);
  Serial.write("Potentiometer 2:");
  Serial.write(pot2.getResistance());
}
4

I don't understand what you changed but it compiled. Thank you.

5

Do a "before and after" comparison of the code and it should become clear.

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6

The "instantiation" - the command to create the object.

X9C103S pot1(1, 2, 3);
X9C103S pot2(4, 5, 6);

It creates pot1 object (instance) and pot2 object (instance). These objects are the thing you direct to do work in your code... "pot1.getResistance(...)" and so on.

7

This is the library "example.ino" file... which shows the ?wrong? way, and will not compile unless the instantiation is move outside loop();

//This example shows how to use the 'getResistance()' method.

#include <X9C103S.h>
// X9C103S pot1(6, 7, 8); // this line should be outside loop(); or it creates "local" instances to loop();
//X9C103S digital potentiometer connected to the Arduino with inc pin to pin 6 ud pin to pin 7 and cs pin to pin 8. Change pin numbers as nessary.
void setup() {
  Serial.begin(9600);
  X9C103S pot1(6, 7, 8); //X9C103S digital potentiometer connected to the Arduino with inc pin to pin 6 ud pin to pin 7 and cs pin to pin 8. Change pin numbers as nessary.
  pot1.initializePot();
}

void loop() {
  pot1.setResistance(45); //Sets the pot resistance to 50. The number can be any number from 1 to 100 (both included).
  pot1.increaseResistance(25); //Increases the pot resistance by 10. The resistance is now at the value 70.
  Serial.write(pot1.getResistance()); //Gets the resistance of the pot and sends it via serial.
}

Should the author be notified? How?

8

I see what you changed. Thanks again. This is for my sons birthday you will have made his day. The plan worked and I have full control of the motors. I can't thank you enough.

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