How to Setup and Change the System Clock on the SAMD21 Microcontroller Family

In this video we look at how to setup and change the system clock on the SAMD21 family of microcontrollers from Microchip / Atmel. This example code is written in C++ and uses direct register access.

Where to access the two versions of the code

• Free version can be found on GitHub: https://github.com/ForceTronics/SamD21_Clock_Setup

• For pay version includes the following additional features:

• Demonstrates how to use the calibration values stored in NVM to tune the 48MHz clock for higher accuracy

• Allows you to change the system clock to 48MHz, 8MHz, 1MHz, and 32768Hz

• Shows how to output the system clock from pin PA27

• Link to code on ForceTronics.com: http://www.forcetronics.com/example-code-for-purchase/samd21-clock-setup-and-control-c-code-example

Pull-up and Pull-down Resistor Tutorial

In this post we take a look at what are pull-up and pull-down resistors, their purpose, and where to use them.

Arduino code from video:
void setup() {
  // put your setup code here, to run once:
  pinMode(3,INPUT);
  pinMode(6,INPUT_PULLUP);
  pinMode(5,INPUT);
  pinMode(4,INPUT);
  pinMode(2,INPUT);
  Serial.begin(57600);

}

void loop() {
  // put your main code here, to run repeatedly:
  Serial.print("This is the pull-up input D6 ");
  Serial.println(digitalRead(6));
  Serial.print("D5 input has no pull-up ");
  Serial.println(digitalRead(5));
   Serial.print("D4 input has no pull-up ");
  Serial.println(digitalRead(4));
  Serial.print("D3 input has no pull-up ");
  Serial.println(digitalRead(3));
   Serial.print("D2 input has no pull-up ");
  Serial.println(digitalRead(2));
  Serial.println();
  delay(1500);
}

How to Protect your Arduino Design (Electrically) Part 1

In this video we look at how to protect your Arduino against different forms of electrical damage and ensure your design is electrically rugged. We will be looking at parts such as current limiting resistors, zenor diodes, and schottky barrier diodes.

Contracting and Consulting Services for Open Source Hardware Design

This video provides an overview of ForceTronics LLC's contracting and consulting services. Whether you are a maker, entrepreneur, or a startup Forcetronics Contracting and Consulting Services can help turn your idea into reality leveraging the power of open source hardware.

If you are interested contact me on twitter or email:

• Twitter: @ForceTronics
• Email: forcetronics@gmail.com

Put “Contracting Services” or “Consulting Services” in the subject line