ATSAMD21-XPRO User Guide Datasheet by Microchip Technology

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AtmeE Atmet \ SMART
SMART ARM-based Microcontrollers
SAM D21 Xplained Pro
USER GUIDE
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. Xplained Pro Quick Start.............................................................................................................. 5
2.2. Design Documentation and Relevant Links................................................................................. 5
3. Xplained Pro.............................................................................................................. 7
3.1. Embedded Debugger................................................................................................................... 7
3.2. Hardware Identification System....................................................................................................8
3.3. Power Sources............................................................................................................................. 8
3.4. Xplained Pro Headers and Connectors........................................................................................9
3.4.1. Xplained Pro Standard Extension Header..................................................................... 9
3.4.2. Xplained Pro Power Header........................................................................................ 10
4. Hardware Users Guide............................................................................................ 11
4.1. Connectors................................................................................................................................. 11
4.1.1. Xplained Pro Standard Extension Headers..................................................................11
4.1.2. Current Measurement Header..................................................................................... 13
4.2. Peripherals................................................................................................................................. 14
4.2.1. Crystal..........................................................................................................................14
4.2.2. Mechanical Buttons..................................................................................................... 14
4.2.3. LED..............................................................................................................................14
4.2.4. USB............................................................................................................................. 14
4.2.5. Serial Flash..................................................................................................................15
4.3. Embedded Debugger Implementation........................................................................................15
4.3.1. Serial Wire Debug........................................................................................................15
4.3.2. Virtual COM Port..........................................................................................................15
4.3.3. Atmel Data Gateway Interface.....................................................................................15
5. Appendix..................................................................................................................17
5.1. Getting Started with IAR.............................................................................................................17
6. Hardware Revision and Known Issues.................................................................... 20
6.1. Identifying Product ID and Revision........................................................................................... 20
6.2. Revision 2...................................................................................................................................20
7. Document Revision History..................................................................................... 21
8. Evaluation Board/Kit Important Notice.....................................................................22
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1. Introduction
1.1. Features
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
1.2. Kit 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
2.1. Xplained Pro Quick Start
Steps to start exploring the Atmel Xplained Pro platform:
1. Download Atmel Studio.
2. Launch Atmel Studio.
3. Connect a USB cable (Standard-A to Micro-B or Micro-AB) between the PC and the DEBUG USB
port on the kit.
When the Xplained Pro MCU kit is connected to your computer for the first time, the operating system will
perform a driver software installation. The driver file supports both 32- and 64-bit versions of Microsoft®
Windows® XP, Windows Vista®, Windows 7, Windows 8, Windows 10, and Windows Server 2012.
Once the Xplained Pro MCU board is powered the green power LED will be lit and Atmel Studio will auto
detect which Xplained Pro MCU- and extension board(s) are connected. Atmel Studio will present
relevant information like datasheets and kit documentation. The kit landing page in Atmel Studio also has
the option to launch Atmel Software Framework (ASF) example applications for the kit. The SAM D21
device is programmed and debugged by the on-board Embedded Debugger and therefore no external
programmer or debugger tool is needed.
2.2. Design Documentation and Relevant Links
The following list contains links to the most relevant documents and software for the SAM D21 Xplained
Pro.
Xplained products - Atmel Xplained evaluation kits are a series of easy-to-use evaluation kits for
Atmel microcontrollers and other Atmel products. For low pin-count devices the Xplained Nano
series provides a minimalistic solution with access to all I/O pins of the target microcontroller.
Xplained Mini kits are for medium pin-count devices and adds Arduino Uno compatible header
footprint and a prototyping area. Xplained Pro kits are for medium to high pin-count devices, they
features advanced debugging and standardized extensions for peripheral functions. All these kits
have on board programmers/debuggers which creates a set of low-cost boards for evaluation and
demonstration of features and capabilities of different Atmel products.
Atmel Studio - Free Atmel IDE for development of C/C++ and assembler code for Atmel
microcontrollers.
Atmel sample store - Atmel sample store where you can order samples of devices.
EDBG User Guide - User guide containing more information about the on-board Embedded
Debugger.
IAR Embedded Workbench® 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.
Atmel QTouch® Library PTC - QTouch Library for Atmel AVR® and ARM®-based microcontrollers.
Atmel QTouch® Composer - Tool for developing capacitive buttons, sliders, and wheels
applications.
Atmel Data Visualizer - Atmel Data Visualizer is a program used for processing and visualizing
data. Data Visualizer can receive data from various sources such as the Embedded Debugger Data
Gateway Interface found on Xplained Pro boards and COM ports.
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Design Documentation - Package containing CAD source, schematics, BOM, assembly drawings,
3D plots, layer plots etc.
Hardware Users Guide in PDF format - PDF version of this User Guide.
SAM D21 Xplained Pro on Atmel web page - Atmel website link.
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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, which 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,
which are connected through a set of standardized headers and connectors. Each extension board has
an identification (ID) chip to uniquely identify which boards are connected to an Xplained Pro MCU board.
This information is used to present relevant user guides, application notes, datasheets, and example
code through Atmel Studio.
3.1. Embedded 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 a Data
Gateway Interface (DGI).
Together with Atmel Studio, the EDBG debugger interface can program and debug the ATSAMD21J18A.
On SAM D21 Xplained Pro, the SWD interface is connected between the EDBG and the
ATSAMD21J18A.
The Virtual COM Port is connected to a UART on the ATSAMD21J18A and provides an easy way to
communicate with the target application through terminal software. It offers variable baud rate, parity, and
stop bit settings. Note that the settings on the ATSAMD21J18A must match the settings given in the
terminal software.
Info:  The virtual COM port in the EDBG requires the terminal software to set the data terminal
ready (DTR) signal to enable the UART pins connected to the ATSAMD21J18A. If the DTR
signal is not enabled the UART pins on the EDBG is kept in high-z (tristate) rendering the COM
port unusable. The DTR signal is set automatically by some terminal software, but it may have
to be manually enabled in your terminal.
The DGI consists of several physical interfaces for communication with the host computer.
Communication over the interfaces is 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. Atmel Data Visualizer is used to send and receive data through DGI.
The EDBG controls two LEDs on SAM D21 Xplained Pro; a power LED and a status LED. The table
below 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
applied to the board.
Activity indicator, LED flashes
when any communication
happens to the EDBG.
Bootloader mode (idle) The power LED and the status LED blinks simultaneously.
Bootloader mode (firmware
upgrade)
The power LED and the status LED blinks in an alternating pattern.
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For further documentation on the EDBG, see the EDBG User Guide.
3.2. Hardware 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 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. The table below 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’
Minimum Voltage [mV] uint16_t 3000
Maximum Voltage [mV] uint16_t 3600
Maximum Current [mA] uint16_t 30
3.3. Power Sources
The SAM D21 Xplained Pro kit can be powered by several power sources as listed in the table below.
Table 3-3. Power Sources for SAM D21 Xplained Pro
Power input Voltage requirements Current requirements Connector marking
External power 5V ±2% (±100mV) for
USB host operation.
4.3V to 5.5V if USB host
operation is not
required.
Recommended
minimum is 1A to be
able to provide enough
current for connected
USB devices and the
board itself.
Recommended
maximum is 2A due to
the input protection
maximum current
specification.
PWR
Embedded debugger
USB
4.4V to 5.25V (according
to USB spec.)
500mA (according to
USB spec.)
DEBUG USB
Target USB 4.4V to 5.25V (according
to USB spec.)
500mA (according to
USB spec.)
TARGET USB
The kit will automatically detect which power sources are available and choose which one to use
according to the following priority:
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1. External power.
2. Embedded Debugger USB.
3. Target USB.
Info:  External power is required when 500mA from a USB connector is not enough to power
the board with possible extension boards. A connected USB device in a USB host application
might easily exceed this limit.
3.4. Xplained Pro Headers and Connectors
3.4.1. Xplained Pro Standard Extension Header
All Xplained Pro kits have one or more dual row, 20-pin, 100mil extension header. Xplained Pro MCU
boards have male headers, while Xplained Pro extensions have their female counterparts. Note that all
pins are not always connected. All connected pins follow the defined pin-out description in the table
below.
The extension headers can be used to connect a variety of Xplained Pro extensions to Xplained Pro MCU
boards or to access the pins of the target MCU on Xplained Pro MCU boards directly.
Table 3-4. Xplained Pro Standard Extension Header
Pin number Name Description
1 ID Communication line to the ID chip on an extension board
2 GND Ground
3 ADC(+) Analog to digital converter, alternatively positive part of differential
ADC
4 ADC(-) Analog to digital converter, alternatively negative part of differential
ADC
5 GPIO1 General purpose I/O
6 GPIO2 General purpose I/O
7 PWM(+) Pulse width modulation, alternatively positive part of differential
PWM
8 PWM(-) Pulse width modulation, alternatively negative part of differential
PWM
9 IRQ/GPIO Interrupt request line and/or general purpose I/O
10 SPI_SS_B/
GPIO
Slave select for SPI and/or general purpose I/O
11 I2C_SDA Data line for I2C interface. Always implemented, bus type.
12 I2C_SCL Clock line for I2C interface. Always implemented, bus type.
13 UART_RX Receiver line of target device UART
14 UART_TX Transmitter line of target device UART
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Pin number Name Description
15 SPI_SS_A Slave select for SPI. Should preferably be unique.
16 SPI_MOSI Master out slave in line of serial peripheral interface. Always
implemented, bus type.
17 SPI_MISO Master in slave out line of serial peripheral interface. Always
implemented, bus type.
18 SPI_SCK Clock for serial peripheral interface. Always implemented, bus type.
19 GND Ground
20 VCC Power for extension board
3.4.2. Xplained Pro Power Header
The power header can be used to connect external power to the SAM D21 Xplained Pro kit. The kit will
automatically detect and switch to any external power if supplied. The power header can also be used as
supply for external peripherals or extension boards. Care must be taken not to exceed the total current
limitation of the on-board regulator when using the 3.3V pin.
Table 3-5. Xplained Pro Power Header
Pin number Pin name Description
1 VEXT_P5V0 External 5V input
2 GND Ground
3 VCC_P5V0 Unregulated 5V (output, derived from one of the input sources)
4 VCC_P3V3 Regulated 3.3V (output, used as main power supply for the kit)
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4. Hardware Users Guide
4.1. Connectors
This chapter describes the implementation of the relevant connectors and headers on SAM D21 Xplained
Pro and their connection to the ATSAMD21J18A. The tables of connections in this chapter also describes
which signals are shared between the headers and on-board functionality.
4.1.1. Xplained Pro Standard Extension Headers
The SAM D21 Xplained Pro headers EXT1, EXT2, and EXT3 offer access to the I/O of the microcontroller
in order to expand the board e.g. by connecting extensions to the board. These headers all comply with
the standard extension header specified in Xplained Pro Standard Extension Header. All headers have a
pitch of 2.54mm.
Table 4-1. Extension Header EXT1
Pin on EXT1 SAM D21 pin Function Shared functionality
1 [ID] - - Communication line to ID chip
on extension board.
2 [GND] - - GND
3 [ADC(+)] PB00 AIN[8]
4 [ADC(-)] PB01 AIN[9]
5 [GPIO1] PB06 GPIO
6 [GPIO2] PB07 GPIO
7 [PWM(+)] PB02 TC6/WO[0]
8 [PWM(-)] PB03 TC6/WO[1]
9 [IRQ/GPIO] PB04 EXTINT[4]
10 [SPI_SS_B/GPIO] PB05 GPIO
11 [TWI_SDA] PA08 SERCOM2 PAD[0] I²C SDA EXT2, EXT3, and EDBG
12 [TWI_SCL] PA09 SERCOM2 PAD[1] I²C SCL EXT2, EXT3, and EDBG
13 [USART_RX] PB09 SERCOM4 PAD[1] UART
RX(1)
14 [USART_TX] PB08 SERCOM4 PAD[0] UART
TX(1)
15 [SPI_SS_A] PA05 SERCOM0 PAD[1] SPI SS
16 [SPI_MOSI] PA06 SERCOM0 PAD[2] SPI MOSI
17 [SPI_MISO] PA04 SERCOM0 PAD[0] SPI MISO
18 [SPI_SCK] PA07 SERCOM0 PAD[3] SPI SCK
19 [GND] - - GND
20 [VCC] - - VCC
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Note: 
1. The SERCOM4 module is shared between EXT1, 2, and 3 UART's, but uses different pins on EXT1
and EXT2/3.
Table 4-2. Extension Header EXT2
Pin on EXT2 SAM D21 pin Function Shared functionality
1 [ID] - - Communication line to ID chip
on extension board.
2 [GND] - - GND
3 [ADC(+)] PA10 AIN[18]
4 [ADC(-)] PA11 AIN[19]
5 [GPIO1] PA20 GPIO
6 [GPIO2] PA21 GPIO
7 [PWM(+)] PB12 TC4/WO[0]
8 [PWM(-)] PB13 TC4/WO[1]
9 [IRQ/GPIO] PB14 EXTINT[14]
10 [SPI_SS_B/GPIO] PB15 GPIO
11 [TWI_SDA] PA08 SERCOM2 PAD[0] I²C SDA EXT1, EXT3, and EDBG
12 [TWI_SCL] PA09 SERCOM2 PAD[1] I²C SCL EXT1, EXT3, and EDBG
13 [USART_RX] PB11 SERCOM4 PAD[1] UART RX
(1)
EXT3
14 [USART_TX] PB10 SERCOM4 PAD[0] UART
TX(1)
EXT3
15 [SPI_SS_A] PA17 SERCOM1 PAD[1] SPI SS
16 [SPI_MOSI] PA18 SERCOM1 PAD[2] SPI MOSI
17 [SPI_MISO] PA16 SERCOM1 PAD[0] SPI MISO
18 [SPI_SCK] PA19 SERCOM1 PAD[3] SPI SCK
19 [GND] - - GND
20 [VCC] - - VCC
Note: 
1. The SERCOM4 module is shared between EXT1, 2, and 3 UART's, but uses different pins on EXT1
and EXT2/3.
Table 4-3. Extension Header EXT3
Pin on EXT3 SAM D21 pin Function Shared functionality
1 [ID] - - Communication line to ID chip
on extension board.
2 [GND] - - GND
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Pin on EXT3 SAM D21 pin Function Shared functionality
3 [ADC(+)] PA02 AIN[0]
4 [ADC(-)] PA03 AIN[1](1) USB ID
5 [GPIO1] PB30 GPIO Onboard LED0
6 [GPIO2] PA15 GPIO Onboard SW0
7 [PWM(+)] PA12 TCC2/WO[0]
8 [PWM(-)] PA13 TCC2/WO[1](2) Serial Flash SS
9 [IRQ/GPIO] PA28 EXTINT[8]
10 [SPI_SS_B/GPIO] PA27 GPIO
11 [TWI_SDA] PA08 SERCOM2 PAD[0] I²C SDA EXT1, EXT2, and EDBG
12 [TWI_SCL] PA09 SERCOM2 PAD[1] I²C SCL EXT1, EXT2, and EDBG
13 [USART_RX] PB11 SERCOM4 PAD[1] UART
RX(3)
14 [USART_TX] PB10 SERCOM4 PAD[0] UART
TX(3)
15 [SPI_SS_A] PB17 SERCOM5 PAD[1] SPI SS
16 [SPI_MOSI] PB22 SERCOM5 PAD[2] SPI MOSI EDBG and Serial Flash
17 [SPI_MISO] PB16 SERCOM5 PAD[0] SPI MISO EDBG and Serial Flash
18 [SPI_SCK] PB23 SERCOM5 PAD[3] SPI SCK EDBG and Serial Flash
19 [GND] - - GND
20 [VCC] - - VCC
Note: 
1. PA03 can be used by USB ID or EXT3 PIN4 by changing the position of the jumper JS300 on J307.
2. PA13 is by default connected to the Serial Flash SS line and is disconnected from the EXT3 PIN8.
This can be changed by moving the 0Ω resistor R314 to R313.
3. The SERCOM4 module is shared between EXT1, 2, and 3 UART's, but uses different pins on EXT1
and EXT2/3.
4.1.2. Current Measurement Header
An angled 1x2, 100mil pin-header marked with MCU current measurement is located at the upper edge of
the SAM D21 Xplained Pro. All power to the ATSAMD21J18A is routed through this header. To measure
the power consumption of the device remove the jumper and replace it with an ammeter.
Caution:  Removing the jumper from the pin-header while the kit is powered may cause the
ATSAMD21J18A to be powered through its I/O pins. This may cause permanent damage to the
device.
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4.2. Peripherals
4.2.1. Crystal
The SAM D21 Xplained Pro kit contains one crystal that can be used as clock source for the SAM D21
device. The crystal has a cut-strap next to it that can be used to measure the oscillator safety factor. This
is done by cutting the strap and adding a resistor across the strap. More information about oscillator
allowance and safety factor can be found in application note AVR4100.
Table 4-4. External 32.768kHz Crystals
Pin on SAM D21 Function
PA00 XIN32
PA01 XOUT32
4.2.2. Mechanical Buttons
SAM D21 Xplained Pro contains two mechanical buttons. One button is the RESET button connected to
the SAM D21 reset line and the other is a generic user configurable button. When a button is pressed it
will drive the I/O line to GND.
Table 4-5. Mechanical Buttons
Pin on SAM D21 Silkscreen text
RESETN RESET
PA15 SW0
4.2.3. LED
There is one yellow LED available on the SAM D21 Xplained Pro board that can be turned on and off.
The LED can be activated by driving the connected I/O line to GND.
Table 4-6. LED Connections
Pin on SAM D21 LED
PB30 Yellow LED0
4.2.4. USB
The SAM D21 Xplained Pro has a micro USB receptable for use with the SAM D21 USB module. To be
able to detect when a USB cable is connected, a GPIO is used to detect the VBUS voltage on the
connector. The USB ID line is used to detect if a host mode cable is connected and will automatically
switch on the power to the USB connector. The I/O connected to USB ID can be used to read the status
of the line or manually override the voltage output. For other modes on the USB ID lines, refer to the USB
organization specifications.
Table 4-7. USB Connections
Pin on SAM D21 USB
PA14 VBUS Detection
PA03 USB ID
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Pin on SAM D21 USB
PA24 USB D-
PA25 USB D+
4.2.5. Serial Flash
The SAM D21 Xplained Pro has an onboard 8Mbit serial flash for non-voltatile storage of data.
Table 4-8. Serial Flash Connections
Pin on SAM D21 Function Serial Flash Shared functionality
PA13 GPIO #CS EXT3 PIN8 (default
disconnected)
PB22 SERCOM5 PAD[2] SPI MOSI SI EXT3 and EDBG
PB16 SERCOM5 PAD[0] SPI MISO SO EXT3 and EDBG
PB23 SERCOM5 PAD[3] SPI SCK SCK EXT3 and EDBG
4.3. Embedded Debugger Implementation
SAM D21 Xplained Pro contains an Embedded Debugger (EDBG) that can be used to program and
debug the ATSAMD21J18A using Serial Wire Debug (SWD). The Embedded Debugger also include a
Virtual Com port interface over UART, an Atmel Data Gateway Interface over SPI and TWI and it monitors
four of the SAM D21 GPIOs. Atmel Studio can be used as a front end for the Embedded Debugger.
4.3.1. Serial Wire Debug
The Serial Wire Debug (SWD) use two pins to communicate with the target. For further information on
how to use the programming and debugging capabilities of the EDBG, see Embedded Debugger.
Table 4-9. SWD Connections
Pin on SAM D21 Function
PA30 SWD clock
PA31 SWD data
4.3.2. Virtual COM Port
The Embedded Debugger acts as a Virtual Com Port gateway by using one of the ATSAMD21J18A
UARTs. For further information on how to use the Virtual COM port see Embedded Debugger.
Table 4-10. Virtual COM Port Connections
Pin on SAM D21 Function
PA22 SERCOM3 PAD[0] UART TXD (SAM D21 TX line)
PA23 SERCOM3 PAD[1] UART RXD (SAM D21 RX line)
4.3.3. Atmel Data Gateway Interface
The Embedded Debugger features an Atmel Data Gateway Interface (DGI) by using either a SPI or I2C
port. The DGI can be used to send a variety of data from the SAM D21 to the host PC. For further
information on how to use the DGI interface see Embedded Debugger.
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Table 4-11. DGI Interface Connections when using SPI
Pin on SAM D21 Function
PB31 SERCOM5 PAD[1] SPI SS (Slave select) (SAM D21 is Master)
PB16 SERCOM5 PAD[0] SPI MISO (Master In, Slave Out)
PB22 SERCOM5 PAD[2] SPI MOSI (Master Out, Slave in)
PB23 SERCOM5 PAD[3] SPI SCK (Clock Out)
Table 4-12. DGI Interface Connections when using I2C
Pin on SAM D21 Function
PA08 SERCOM2 PAD[0] SDA (Data line)
PA09 SERCOM2 PAD[1] SCL (Clock line)
Four GPIO lines are connected to the Embedded Debugger. The EDBG can monitor these lines and time
stamp pin value changes. This makes it possible to accurately time stamp events in the SAM D21
application code. For further information on how to configure and use the GPIO monitoring features see
Embedded Debugger.
Table 4-13. GPIO Lines Connected to the EDBG
Pin on SAM D21 Function
PA27 GPIO0
PA28 GPIO1
PA20 GPIO2
PA21 GPIO3
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5. Appendix
5.1. Getting Started with IAR
IAR Embedded Workbench® for ARM® is a proprietary high efficiency compiler not based on GCC.
Programming and debugging of Xplained Pro kits are supported in IAR Embedded Workbench for ARM
using the common CMSIS-DAP interface. Some initial settings have to be set up in the project to get the
programming and debugging to work.
The following steps will explain how to get your project ready for programming and debugging:
1. Make sure you have opened the project you want to configure. Open the OPTIONS dialog for the
project.
2. In the category General Options, select the Target tab. Select the device for the project or, if not
listed, the core of the device.
3. In the category Debugger, select the Setup tab. Select CMSIS DAP as the driver.
4. In the category Debugger, select the Download tab. Check the check box for Use flash loader(s)
option.
5. In the category Debugger > CMSIS DAP, select the Setup tab. Select System (default) as the
reset method.
6. In the category Debugger > CMSIS DAP, select the JTAG/SWD tab. Select SWD as the interface
and optionally select the SWD speed.
Figure 5-1. Select Target Device
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Figure 5-2. Select Debugger
Figure 5-3. Configure Flash Loader
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Figure 5-4. Configure Reset
Figure 5-5. Configure Interface
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6. Hardware Revision and Known Issues
6.1. Identifying Product ID and Revision
The revision and product identifier of Xplained Pro boards can be found in two ways; either through Atmel
Studio or by looking at the sticker on the bottom side of the PCB.
By connecting an Xplained Pro MCU board to a computer with Atmel Studio running, an information
window will pop up. The first six digits of the serial number, which is listed under kit details, contain the
product identifier and revision. Information about connected Xplained Pro extension boards will also
appear in the Atmel Kit's window.
The same information can be found on the sticker on the bottom side of the PCB. Most kits will print the
identifier and revision in plain text as A09-nnnn\rr, where nnnn is the identifier and rr is the revision.
Boards with limited space have a sticker with only a QR-code, which contains a serial number string.
The serial number string has the following format:
"nnnnrrssssssssss"
n = product identifier
r = revision
s = serial number
The product identifier for SAM D21 Xplained Pro is A09-2130.
6.2. Revision 2
Revision 2 of SAM D21 Xplained Pro is the initial released version.
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7. Document Revision History
Doc. rev. Date Comment
42220B 04/2016 Added Getting Started with IAR.
42220A 02/2014 Initial document release.
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8. Evaluation Board/Kit Important Notice
This evaluation board/kit is intended for use for FURTHER ENGINEERING, DEVELOPMENT,
DEMONSTRATION, OR EVALUATION PURPOSES ONLY. It is not a finished product and may not
(yet) comply with some or any technical or legal requirements that are applicable to finished products,
including, without limitation, directives regarding electromagnetic compatibility, recycling (WEEE), FCC,
CE or UL (except as may be otherwise noted on the board/kit). Atmel supplied this board/kit "AS IS",
without any warranties, with all faults, at the buyer's and further users' sole risk. The user assumes all
responsibility and liability for proper and safe handling of the goods. Further, the user indemnifies Atmel
from all claims arising from the handling or use of the goods. Due to the open construction of the
product, it is the user's responsibility to take any and all appropriate precautions with regard to
electrostatic discharge and any other technical or legal concerns.
EXCEPT TO THE EXTENT OF THE INDEMNITY SET FORTH ABOVE, NEITHER USER NOR ATMEL
SHALL BE LIABLE TO EACH OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR
CONSEQUENTIAL DAMAGES.
No license is granted under any patent right or other intellectual property right of Atmel covering or
relating to any machine, process, or combination in which such Atmel products or services might be or
are used.
Mailing Address: Atmel Corporation
1600 Technology Drive
San Jose, CA 95110
USA
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© 2016 Atmel Corporation. / Rev.: Atmel-42220B-SAM-D21-Xplained-Pro_User Guide-04/2016
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