Tag Archives: SAM D20 Xplained Pro Kit

Please explain to Grandma: What’s the SAM D20 Xplained Dev Board?

My side of the family is very small. I have two parents and a sister, and it stops just about there. My girlfriend’s family, on the other hand, is quite the opposite. A large family means regular family events, and after close to ten years, I still haven’t met everyone. This is just one of those occasions, where I smile, and pretend not to be terrified.

There are a few people walking around the room, but the three mains congregation points are in front of the huge fireplace where apparently someone has attempted to put in a small tree, and just push it in as the end burns away. The table is full of food, and quite a few people are nibbling on delicious snacks. Then there is apparently a line of grandmothers at the back of the room. I hear my name spoken from this part of the room, and I turn around to see five grandmothers looking at me, as well as one or two unknown members of the family. I think I’m supposed to say something.

Excuse me?

– I said that you had just written a book.

Yes, indeed.

– What is it about? Asks one of the grandmothers. They all look at me.

We’ve all been there, a family reunion, where you suddenly become the center of attention. I am subjected to a two hundred kilowatt neon blue stare, the sort of look you get when you are asked the famous family questions; When are you going to get a haircut? When are you going to get a job? And when are you going to come over and see the neighbors because they have this fantastic son/daughter who is single and has just had this promotion at work! I think I’m losing weight just being subjected to this look. Here we go. It is a technical book—about ARM processors.

– Oh, that’s nice!

That one phrase says it all. I start counting under my breath. Two… Three…

– And, um, what exactly is an ARM processor?

I start to explain that it is a type of processor, the “brains” if you will of modern machines. A few weeks ago, I was asked to explain the IoT to someone, and that person is here, practically jumping up and down in excitement.

– Show them the Internet thingy!

Very quietly, from the privacy of my own head, I sigh. Internet of Things, not the “Internet Thingy”. Please excuse me while I go and fetch it. I also take the opportunity to drink an ice-cold glass of water.

Atmel's SAM D20  Xplained Development Board

Atmel’s SAM D20 Xplained Development Board

On returning, I show them the board, an Atmel SAM D20 evaluation board that I used for my book. I explain that the SAM D20 is based on an ARM processor, using Atmel’s technology, and that the entire board is used as a prototyping device, capable of hundreds of applications, depending on your imagination. I also point out the SAM D20 itself; this little black thing here, the size of a thumbnail that is the processor…

– That isn’t a processor.

I come from a very technology-phobic family. My mother spent weeks looking for a microwave with a single button because she doesn’t want to have to enter any information at all, not even the amount of seconds. My father’s grasp of computers is fairly limited; when asked how much RAM he has, his answer is “Enough, I suppose”. It’s the same for every single component. He uses them because he doesn’t have a choice. He still has a telex machine in his office. It’s almost a miracle I got into technology in the first place. With such a family, I’m used to translating, and I had already prepared myself for just about any question possible on my book, but I wasn’t expecting this. Excuse me?

– I said that isn’t a processor.

Umm… If you really want to be complicated, I suppose you could argue that it is a microcontroller, since it is based on the Cortex-M0+, but I don’t think that is what she means. What do you mean?

– I changed the processor on my computer a few weeks ago, and a processor is much larger.

The grandmother line has just shifted looks, and is once again analyzing m every move. My opponent is getting more approving nods than I am.

Well, yes, indeed, the processor on your computer is bigger, and if that is what you are looking for, it is better, faster, and just about everything you could imagine. The only problem is… bigger does not mean better. I’ve been in contact with Atmel for some time now, and I’ve been using their products for even longer. I know that they have an impressive range of processor families, and in each family is an even bigger list of members. There is a processor for just about every need. First things first, I need to sort out the Grandmother look.

Okay, so the processor on your computer is larger, indeed. The only thing is, you don’t use it for the same thing, do you?

– You mean that what you have in your hand isn’t powerful?

No, that isn’t what I mean. It is powerful enough. It all depends on what you need. The SAM D20 is an excellent microcontroller, and at 48MHz, it is more than powerful enough for most applications. That gives me an idea…

What kind of car do you drive?

– A medium range, why?

What, you don’t have a sports car? Why not? They are better!

– But I don’t need a sports car!

Exactly. There is a lot of choice, and you decided to go with a model that suits your needs; budget, comfort, utility. If you wanted better, you could have gone with a sports car. You might even have decided to buy a lorry, I mean, the engine is more powerful. It is the same thing with processors. You have a high-end processor in your computer, but do you really want a $500 processor on your wrist, using up so much power that you need a 5-pound battery on your back just to tell the time? The SAM D20 is ultra low powered, you could keep it on your wrist for weeks, maybe even months without a recharge, and it has more than enough power to display the time, and also some bonus features like a thermometer, UV sensor, heart beat monitor, and to record your physical activity and upload that onto your flashy fast computer. It doesn’t heat up as much, and won’t burn your wrist. Plus, it costs a fraction of the price.


I get a majority of approving nods. The granny stare now shifts back to the other person.

– Yes, but processors are getting faster, so why buy something that is slow?

It isn’t slow, not even close. It runs at 48MHz. Let me remind you that your first computer probably ran at 4MHz, and you were happy with that. Processors aren’t only based on their speed in megahertz, and ARM processors are exceptionally fast per megahertz compared to some other design. Also, Atmel added in even more intelligence, making this a very fast and efficient system. Atmel’s Event System makes this ideal for automation, allowing peripherals to react to external events without slowing down processing.

Now, I only have one more person to convince.

– So why would I need one?

Not only do you need one, but you already have several processors like this. Your microwave has one, your car has several to control braking, the radio, the on-board computer and even the different sensors. The world is full of tiny processors, helping us live our lives. And this tiny processor on the SAM D20 Xplained Pro board is one of hundreds of designs from Atmel. My book talks about just some of those designs, and also talks about the SAM D20 Xplained Pro, Atmel’s IDP (Integration Development Platform), and how easy it is to get a project up and running. Five approval nods. I won this one.

– I see what you mean. By the way, when are you going to marry your girlfriend?

Red alert! Five approval nods. I lost this one. Time to go!

Video: Building a GPS tracker with Atmel’s SAM D20 MCU

A GPS tracking unit uses the Global Positioning System to determine and record the precise location of a vehicle, device or individual. Key design requirements for a GPS tracker include a small form factor, low power consumption and flexible connectivity options.

Atmel’s versatile SAM D20 ARM Cortex-M0+ based microcontroller (MCU) can be used to power such a device, taking all of the above-mentioned design requirements into account.

Indeed, the SAM D20 MCU – embedded with serial communication modules (SERCOM) and low power consumption – provides the flexibility, connectivity and low power required for GPS tracker applications.

In terms of low power consumption, the SAM D20 boasts <150µA/MHz in active (CoreMark) and <2µA with RTC and full RAM retention. Meanwhile, the peripheral event system and intelligent peripherals with Atmel SleepWalking technology further reduces CPU activity and power sipping.

It should also be noted that the SAM D20 MCU offers design engineers 6 highly flexible serial communication modules (SERCOM), each configurable to operate as USART, I2C and SPI – thereby facilitating easy and flexible connection to external sensors, memories, PCs and wireless modules.

Atmel supports a wide range of dev tools and software, including FreeRTOS, Atmel Studio 6 (free IDE with GCC compiler), Atmel Software Framework (free SW libraries of production ready source code), Atmel Gallery (open to extensions) and the SAM D20 Xplained Pro Kit which is packaged with programmer and debugger, as well as connectors for expansion wings.

Interested in learning more? You can check out Atmel’s SAM D20 GPS tracker reference design here.