Atmel SAM D21 Xplained Pro User guide

USER GUIDE

Atmel SAM D21 Xplained Pro

Preface

The Atmel® SAM D21 Xplained Pro evaluation kit is a hardware platform to evaluate the ATSAMD21J18A microcontroller.

Supported by the Atmel Studio integrated development platform, the kit provides easy access to the features of the Atmel ATSAMD21J18A and explains how to integrate the device in a custom design.

The Xplained Pro MCU series evaluation kits include an on-board Embedded Debugger, and no external tools are necessary to program or debug the ATSAMD21J18A.

The Xplained Pro extension kits offers additional peripherals to extend the features of the board and ease the development of custom designs.

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Table of Contents

Preface		..........................................................................................		1
1.	Introduction ..............................................................................			3
	1.1.	Features	..............................................................................	3
	1.2.	Kit Overview .........................................................................		3
2.	Getting ........................................................................Started			5
	2.1. ...........................................................................	Quick - start		5
	2.2. .................................................................	Connecting the Kit		5
	2.3. ..................................Design Documentation and Related Links			5
3.	Xplained ............................................................................Pro			6
	3.1. .............................................................	Embedded Debugger		6
	3.2. ................................................	Hardware Identification System		6
	3.3. .......................................................................	Power Supply		7
	......................	3.3.1. Measuring SAM D21 Power Consumption		7
	3.4. ...........................................Standard Headers and Connectors			7
	......................	3.4.1. Xplained Pro Standard Extension Header		7
	........................................	3.4.2. Xplained Pro Power Header		8
4.	Hardware ...........................................................User Guide			10
	4.1. .........................................................................	Connectors		10
	.............................................	4.1.1.	I/O Extension Headers	10
	4.2. .........................................................................	Peripherals		11
	...................................................................	4.2.1.	Crystal	11
	..................................................	4.2.2.	Mechanical Buttons	12
	......................................................................	4.2.3.	LED	12
	......................................................................	4.2.4.	USB	12
	............................................................	4.2.5.	Serial Flash	12
	4.3. ......................................	Embedded Debugger Implementation		13
	...................................................	4.3.1.	Serial Wire Debug	13
	.....................................................	4.3.2.	Virtual COM Port	13
	...................................	4.3.3. Atmel Data Gateway Interface		13
5.	Hardware .....................Revision History and Known Issues			14
	5.1. .........................................Identifying Product ID and Revision			14
	5.2. ..........................................................................	Revision 2		14
6.	Document ...................................................Revision History			15
7.	Evaluation ..................................Board/Kit Important Notice			16

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1.Introduction

1.1Features

●Atmel ATSAMD21J18A microcontroller

●Embedded debugger (EDBG)

●USB interface

●Programming and debugging on board SAM D21 through Serial Wire Debug (SWD)

●Virtual COM-port interface to target via UART

●Atmel Data Gateway Interface (DGI) to target via SPI and TWI

●Four GPIOs connected to target for code instrumentation

●Digital I/O

●Two mechanical buttons (user and reset button)

●One user LED

●Three extension headers

●Three possible power sources

●External power

●Embedded debugger USB

●Target USB

●32kHz crystal

●USB interface, device and reduced host mode

●8Mbit Serial Flash

1.2Kit Overview

The Atmel SAM D21 Xplained Pro evaluation kit is a hardware platform to evaluate the Atmel ATSAMD21J18A.

The kit offers a set of features that enables the ATSAMD21J18A user to get started using the ATSAMD21J18A peripherals right away and to get an understanding of how to integrate the device in their own design.

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Figure 1-1. SAM D21 Xplained Pro Evaluation Kit Overview

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2.Getting Started

2.1Quick-start

3 Steps to start exploring the Atmel Xplained Pro Platform

●Download and install Atmel Studio1

●Launch Atmel Studio

●Connect a Micro-B cable to the DEBUG USB port

2.2Connecting the Kit

When connecting Atmel SAM D21 Xplained Pro to your computer for the first time, the operating system will do

a driver software installation. The driver file supports both 32-bit and 64-bit versions of Microsoft® Windows® XP and Windows 7.

Once connected the green power LED will be lit and Atmel Studio will autodetect which Xplained Pro evaluationand extension kit(s) that's connected. You'll be presented with relevant information like datasheets and kit documentation. You also have the option to launch Atmel Software Framework (ASF) example applications. The target device is programmed and debugged by the on-board Embedded Debugger and

no external programmer or debugger tool is needed. Refer to the Atmel Studio user guide2 for information regarding how to compile and program the kit.

2.3Design Documentation and Related Links

The following list contains links to the most relevant documents and software for SAM D21 Xplained Pro.

1.Xplained Pro products 3 - Atmel Xplained Pro is a series of small-sized and easy-to-use evaluation kits for 8- and 32-bit Atmel microcontrollers. It consists of a series of low cost MCU boards for evaluation and demonstration of features and capabilities of different MCU families.

2.SAM D21 Xplained Pro User Guide 4 - PDF version of this User Guide.

3.SAM D21 Xplained Pro Design Documentation 5 - Package containing schematics, BOM, assembly drawings, 3D plots, layer plots etc.

4.EDBG User Guide 6 - User guide containing more information about the onboard Embedded Debugger.

5.Atmel Studio 7 - Free Atmel IDE for development of C/C++ and assembler code for Atmel microcontrollers.

6.IAR Embedded Workbench® 8 for ARM®. This is a commercial C/C++ compiler that is available for ARM. There is a 30 day evaluation version as well as a code size limited kick-start version available from their website. The code size limit is 16KB for devices with M0, M0+ and M1 cores and 32KB for devices with other cores.

7.Atmel sample store 9 - Atmel sample store where you can order samples of devices.

1http://www.atmel.com/atmelstudio

2http://www.atmel.com/atmelstudio

3http://www.atmel.com/XplainedPro

4http://www.atmel.com/Images/Atmel-42220-SAMD21-Xplained-Pro_User-Guide.pdf

5http://www.atmel.com/Images/Atmel-42220-SAMD21-Xplained-Pro_User-Guide.zip

6http://www.atmel.com/Images/Atmel-42096-Microcontrollers-Embedded-Debugger_User-Guide.pdf

7http://www.atmel.com/atmelstudio

8http://www.iar.com/en/Products/IAR-Embedded-Workbench/ARM/

9http://www.atmel.com/system/samplesstore

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3.Xplained Pro

Xplained Pro is an evaluation platform that provides the full Atmel microcontroller experience. The platform consists of a series of Microcontroller (MCU) boards and extension boards that are integrated with Atmel Studio, have Atmel Software Framework (ASF) drivers and demo code, support data streaming and more. Xplained Pro MCU boards support a wide range of Xplained Pro extension boards that are connected through a set of standardized headers and connectors. Each extension board has an identification (ID) chip to uniquely identify which boards are mounted on a Xplained Pro MCU board. This information is used to present relevant user guides, application notes, datasheets and example code through Atmel Studio. Available Xplained Pro MCU and extension boards can be purchased in the Atmel Web Store1.

3.1Embedded Debugger

The SAM D21 Xplained Pro contains the Atmel Embedded Debugger (EDBG) for on-board debugging. The EDBG is a composite USB device of three interfaces; a debugger, Virtual COM Port and Data Gateway Interface (DGI).

In conjunction with Atmel Studio, the EDBG debugger interface can program and debug the ATSAMD21J18A. On the SAM D21 Xplained Pro, the SWD interface is connected between the EDBG and the ATSAMD21J18A.

The Virtual COM Port is connected to a UART port on the ATSAMD21J18A (see section “Embedded Debugger Implementation” on page 13 for pinout), and provides an easy way to communicate with the target

application through simple terminal software. It offers variable baud rate, parity and stop bit settings. Note that the settings on the target device UART must match the settings given in the terminal software.

The DGI consists of several physical data interfaces for communication with the host computer. See section “Embedded Debugger Implementation” on page 13 for available interfaces and pinout. Communication over the interfaces are bidirectional. It can be used to send events and values from the ATSAMD21J18A, or as a generic printf-style data channel. Traffic over the interfaces can be timestamped on the EDBG for more

accurate tracing of events. Note that timestamping imposes an overhead that reduces maximal throughput. The DGI uses a proprietary protocol, and is thus only compatible with Atmel Studio.

The EDBG controls two LEDs on SAM D21 Xplained Pro, a power LED and a status LED. Table 3-1, “EDBG LED Control” on page 6 shows how the LEDs are controlled in different operation modes.

Table 3-1. EDBG LED Control

	Operation mode	Power LED	Status LED
	Normal operation	Power LED is lit when power is	Activity indicator, LED flashes
		applied to the board.	every time something happens on
			the EDBG.
	Bootloader mode (idle)	The power LED and the status LED blinks simultaneously.
	Bootloader mode (firmware	The power LED and the status LED blinks in an alternating pattern.
	upgrade)

For further documentation on the EDBG, see the EDBG User Guide2.

3.2Hardware Identification System

All Xplained Pro compatible extension boards have an Atmel ATSHA204 CryptoAuthentication™ chip mounted. This chip contains information that identifies the extension with its name and some extra data. When an Xplained Pro extension board is connected to an Xplained Pro MCU board the information is read and sent

to Atmel Studio. The Atmel Kits extension, installed with Atmel Studio, will give relevant information, code examples and links to relevant documents. Table 3-2, “Xplained Pro ID Chip Content” on page 6 shows the data fields stored in the ID chip with example content.

Table 3-2. Xplained Pro ID Chip Content

	Data Field	Data Type	Example Content
	Manufacturer	ASCII string	Atmel’\0’
	Product Name	ASCII string	Segment LCD1 Xplained Pro’\0’
	Product Revision	ASCII string	02’\0’
	Product Serial Number	ASCII string	1774020200000010’\0’

1http://store.atmel.com/CBC.aspx?q=c:100113

2http://www.atmel.com/Images/Atmel-42096-Microcontrollers-Embedded-Debugger_User-Guide.pdf

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