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Overview

This tutorial will teach you how to setup a DC motor with the Satellite boards built-in Mosfet and how to control the motor speed using Analog input.

Components

Arduino
A/B USB connectors
Museduino Shield
2 Satellite boards
CAT5 cable
DC Motor
10k Potentiometer
screw driver

Setup

First, complete the instructions for the DC Motor tutorial.

Now let’s add potentiometer on Arduino Analog Pin A0 using a second Satellite board. Use the Analog Select chart to configure the jumper shunts in the correct Down position.

Once you’ve configured the jumpers, we need to wire the potentiometer to the following screw terminal configuration:

1 – Power
2 – Direct Signal
4 – Ground

Each Satellite is designed with 2 RJ-45 connectors allowing multiple Satellite boards to be daisy chained with distance between sensors/actuators.

Code

Copy code below or download from Github. Upload the sketch.

/*
  Museduino | DC Motor Tutorial
  Control the speed of a DC moto with a potentiometer
*/

//satellite Pin 1 on Port A
int s1A = A0;

//satellite Pin 3 on Port A 
int s3A = 9; //default arduino pin is D8, use Analog Select to swap with D9~

int motorSpeed = 0; //motor speed value

// the setup routine runs once when you press reset:
void setup() { 
  
  Serial.begin(9600);
  
  // initialize potentiometer as input and the motor pin as an output.
  pinMode(s1A, INPUT);
  pinMode(s3A, OUTPUT); 

}

// the loop routine runs over and over again forever:
void loop() {
  
  //read value from potentiometer
  motorSpeed = analogRead(s1A);
  
  //map value from 0 (off) to 255 (on)
  motorSpeed = map(motorSpeed, 1023, 0, 0, 255);
  
  Serial.println(motorSpeed);
  
  //if motorSpeed > 0, set the speed
  if(motorSpeed > 0) {
    analogWrite(s3A, motorSpeed);
  } else {
    //stop the motor
    digitalWrite(s3A, LOW);
  }
  
  
}

Need More Satellite I/O? Checkout the new Port Extender Satellite board.

Overview

This tutorial will teach you how to setup a DC motor with the Satellite boards built-in Mosfet and how to control the motor speed using Serial input.

Components

Arduino
A/B USB connectors
Museduino Shield
Satellite board
CAT5 cable
DC Motor
screw driver

Setup

For this tutorial we are going to use Arduino pin D9~.

D9~ pin can be accessed on either Satellite I/O 3 on Port A or Satellite I/O 5 on Port B. Place PWM Select jumpers in the default Up position so that D9~ is available on Port A.

Before we get started, take a look at the Pin Configuration Chart.

Both the Smorgasboard and External Power boards have a built-in Mosfet, which is a type of transistor meant for actuators that require more power than an Arduino digital output can handle directly.

The Arduino can only provide 40mA at 5V on its digital pins. Most motors require more current and/or voltage to operate. A transistor can act as a digital switch, enabling the Arduino to control loads with higher electrical requirements.

With a mosfet, you have an “in” called the Source, an “out” called the Drain, and a “control” called the Gate. When you send a HIGH signal to the gate (Signal pin), the transistor switches and allows current or voltage to flow from the source (in) to the drain (out). Ground is connected to the transistor’s drain. A pull-down resistor holds the gate low when the signal pin is LOW.

Learn more about transistors and mosfets here:
https://learn.adafruit.com/transistors-101

When working with actuators that have a coil (DC motors, relay, solenoid), it is also important to use a “snubber” or “flyback” Diode, which is a diode used to eliminate negative voltage spikes when power is suddenly reduced or removed.

To prevent damage to the Mosfets on your Satellite boards, the latest versions now include a diode and a pull-down resistor to complete the circuit. For older versions, you must use a diode in parallel with the motor (between screw terminal pins 1 – power and 2- signal) and a 10k pull-down resistor (between screw terminal pins 3 – direct signal and 4 – ground).

Now let’s hook up the motor. DC motors can usually run with either polarity but direction of rotation will be reversed. Connect one wire of your motor to screw terminal pin 1 for power and the other wire to screw terminal pin 2 for Signal with an Open Drain to Ground.

This circuit is okay to use with a 5v hobby motor. For motors requiring 6v or higher, use External Power.

Code

This tutorial uses Pulse-width modulation (PWM) to simulate a variable supply voltage. The voltage supplied to a DC motor controls its speed.

Copy code below or download from Github.

Upload the sketch and open the serial monitor to set a motor speed value of 0 to 255.

/*
  Museduino | DC Motor Tutorial
  Set the speed of a DC motor using Serial
*/

//satellite Pin 3 on Port A 
int s3A = 9; //default arduino pin is D8, use PWM Select to swap with D9~


// the setup routine runs once:
void setup() { 
  // initialize the serial communication
  Serial.begin(9600);
  
  // initialize motor pin as an output
  pinMode(s3A, OUTPUT); 

  Serial.println("Speed 0 to 255");


}

// the loop routine runs over and over again forever:
void loop() {
	
    int speed; //motor speed value must be 0 to 255
		
    // check if data has been sent over serial
    if (Serial.available()) {
      // parse the most recent int (0 to 255):
      speed = Serial.parseInt();

      if (speed >= 0 && speed <= 255) {
         //set the speed of the motor  
         analogWrite(s3A, speed);
      }
	  
    }
  
}

Want to control the speed of the motor with an analog input?

Overview

This tutorial will teach you how to use the External Power Satellite board with a NeoPixel RGB LED Strip.

Components

Arduino
A/B USB cable
Museduino Shield
Museduino External Power board
CAT5 cable
NeoPixel RGB LED Strip 
5v 2 amp Switching Power Supply
300-500 ohm resistor
1000µF, 6.3V or higher capacitor
screwdriver

Setup

For detailed information about Neopixels, please review the Adafruit NeoPixel Uberguide. For this tutorial, we use a 1 meter NeoPixel LED Strip (60pixel/meter). The Neopixel Uberguide suggests a power supply with a minimum of 1.2 amps. We recommend using a 5V 2amp Switching Power Supply.

Take a look at the External Power satellite board. Notice that the board is equipped with a DC barrel jack and a 2pin screw terminal for power and ground. Either connection can be used as an external power source. When an external power source is connected, the LED indicating 6-12V will be on. The board also contains External Power Jumpers on Satellite I/O pins 3, 4, 5 which allow you to switch from 5V to the 6-12V supply.

To connect a NeoPixel Strip, we are going to use Arduino Digital Pin 6 (Satellite Pin 5 on Port A).

Locate Satellite I/O pin 5 on the External Power board. Based on the Satellite pin configuration, you will use screw terminal block pins 1 (power), 3 (direct signal), and 4 (ground).

The Neopixel Strip has four colored wires; red (power), white (signal/data), and two black (ground). We will also use a 470 ohm resistor between the microcontroller signal pin and the Neopixel data input pin to help prevent spikes on the data line that can damage the first pixel. Feel free to use a breadboard for this exercise or solder the resistor in series with the signal/data wire.

It is best practice to avoid connecting NeoPixels to a live circuit. Always connect ground first, then +5V, then data. Disconnect in the reverse order. A small screwdriver is needed to tighten/loosen the screw terminals.

Connect both black Neopixel wires to screw terminal pin 4 (ground), the red Neopixel wire to screw terminal pin 1 (power), and the white Neopixel wire to screw terminal pin 3 (direct signal).

Before connecting NeoPixels to the power source, use the 2 pin screw terminal to connect a capacitor across the + and – terminals. This will help buffer sudden changes in the current drawn by the strip.

Next, find the External Power jumper directly above satellite pin 5. Move the jumper shunt to the right to switch to external power.

Now plugin the 5v 2amp Switching Power Supply to the DC barrel jack.

Via CAT5 cable, connect the External Power satellite power board to Port A. Then connect your Arduino via usb to upload the program to control the NeoPixel strip.

Code

Download the Adafruit_NeoPixel library. For this tutorial, upload the strand test sketch to your Arduino.

Want to use DC motors with Museduino? Go to the next tutorial.

Overview

This tutorial will teach you how to use Analog Select Jumpers with a potentiometer and servo motor.

Components

Arduino
A/B USB cable
Museduino Shield
2 Museduino Satellite Boards
CAT5 cable
servo motor
screw driver
prototyping wire

Setup

Before we get started, let’s learn about the Analog Select feature on the Main Shield. Locate the header pins (2×3 block) labeled “ANALOG” between the RJ-45 connecters.

The Analog Select feature on the main shield is designed to swap pins between two ports. The Analog Select switch on the left of the main shield can be used to swap Satellite I/O pin 1 on Port A with Satellite I/O pin 3 on B. The Analog Select switch on the right of the main shield can be used to swap Satellite Pin 1 on Port C with Satellite I/O pin 3 on D.

In order to use the switches, you must use the jumper shunts provided. There are two jumper shunts for each Analog Select switch (2×3 block) and they both must be placed in an “Up” or “Down” position.

Below is a chart to assist with the proper jumper configuration:

Now that you have learned about the Analog Select feature, let’s use a potentiometer on Arduino Pin A0.

The chart shows that Arduino Pin A0 is available from Satellite I/O pin 1 on Port A (default UP position). Since the Analog jumpers can be used to swap Satellite I/O pin 3 on Port C with Satellite I/O pin 5 on D, this means we can swap A0 and D11~. Place the jumper shunts in a “Down” position to make A0 available from Satellite Pin 1 on Port A.

Satellite I/O pins 1 and 2 are intended for use with Analog Inputs. Connect a potentiometer to Satellite I/O pin 1. 

We will need to use Power (screw terminal  1), Signal (screw terminal 2 or 3), Ground (screw terminal 4) on either a Smorgasboard or External Power Board. Connect the Satellite board to Port A.

Next, connect a servo motor to Arduino pin D9~ ( Satellite I/O pin 5 on Port B). We will need to use Power (screw terminal  1), Signal (screw terminal 3), Ground (screw terminal 4) on either a Smorgasboard or External Power Board. Connect the Satellite board to Port B.

Code

Copy code below or download from Github.

Upload the sketch.

/* 
Museduino | Servo Motors (PWM Select) Tutorial 
Control servo position using a potentiometer (variable resistor) 
*/

#include "servo.h"
 
Servo servo;  // create servo object to control a servo
 
int s1A = A0;  // analog pin used to connect the potentiometer - Satellite Pin 1 on Port A

int s5B = 9; // digital/pwm pin used to connect the servo - Satellite I/O Pin 5 on Port B

int val; // variable to read the value from the analog pin 
 
void setup() 
{ 
  servo.attach(s5B);  // attaches the servo on D9~ to the servo object (satellite pin 5 on B)
} 
 
void loop() 
{ 
  val = analogRead(s1A);            // reads the value of the potentiometer (value between 0 and 1023) 
  val = map(val, 0, 1023, 0, 180);  // remap to use it with the servo (value between 0 and 180) 
  servo.write(val);                 // sets the servo position according to the scaled value 
  delay(15);                        // waits for the servo to get there 
} 

Want to use Neopixels with Museduino?