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.
42220A-MCU-02/2014
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
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
2
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.
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
3
Figure 1-1. SAM D21 Xplained Pro Evaluation Kit Overview
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
4
2. Getting Started
2.1 Quick-start
3 Steps to start exploring the Atmel Xplained Pro Platform
● Download and install Atmel Studio
● Launch Atmel Studio
● Connect a Micro-B cable to the DEBUG USB port
2.2 Connecting 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
evaluation- and 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.
1
®
2.3 Design 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.
1
http://www.atmel.com/atmelstudio
2
http://www.atmel.com/atmelstudio
3
http://www.atmel.com/XplainedPro
4
http://www.atmel.com/Images/Atmel-42220-SAMD21-Xplained-Pro_User-Guide.pdf
5
http://www.atmel.com/Images/Atmel-42220-SAMD21-Xplained-Pro_User-Guide.zip
6
http://www.atmel.com/Images/Atmel-42096-Microcontrollers-Embedded-Debugger_User-Guide.pdf
7
http://www.atmel.com/atmelstudio
8
http://www.iar.com/en/Products/IAR-Embedded-Workbench/ARM/
9
http://www.atmel.com/system/samplesstore
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
5
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.
3.1 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 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
applied to the board.
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.
3.2 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 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’
Activity indicator, LED flashes
every time something happens on
the EDBG.
1
http://store.atmel.com/CBC.aspx?q=c:100113
2
http://www.atmel.com/Images/Atmel-42096-Microcontrollers-Embedded-Debugger_User-Guide.pdf
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
6
Data Field Data Type Example Content
Minimum Voltage [mV] uint16_t 3000
Maximum Voltage [mV] uint16_t 3600
Maximum Current [mA] uint16_t 30
3.3 Power Supply
The SAM D21 Xplained Pro kit can be powered either by USB or by an external power source through the 4pin power header, marked PWR. This connector is described in “Xplained Pro Power Header” on page 8.
The available power sources and specifications are listed in Table 3-3, “Power Sources for SAM D21 Xplained
Pro” on page 7.
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
Embedded debugger
USB
4.4V to 5.25V
(according to USB spec)
Target USB 4.4V to 5.25V
(according to USB spec)
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.
500mA (according to
USB spec)
500mA (according to
USB spec)
PWR
DEBUG USB
TARGET USB
The kit will automatically detect which power sources are available and choose which one to use according to
the following priority:
1. External power
2. Embedded debugger USB
3. Target USB
Note
External power is required when the 500mA through the USB connector is not enough to power a
connected USB device in a USB host application.
3.3.1 Measuring SAM D21 Power Consumption
As part of an evaluation of the SAM D21 it can be of interest to measure its power consumption. Because the
device has a separate power plane (VCC_MCU_P3V3) on this board it is possible to measure the current
consumption by measuring the current that is flowing into this plane. The VCC_MCU_P3V3 plane is connected
via a jumper to the main power plane (VCC_TARGET_P3V3) and by replacing the jumper with an ammeter it is
possible to determine the current consumption. To locate the current measurement header, refer to Figure 1-1,
“SAM D21 Xplained Pro Evaluation Kit Overview” on page 4.
Warning
Do not power the board without having the jumper or an ammeter mounted. This can cause the
SAM D21 to be powered through its I/O pins and cause undefined operation of the device.
3.4 Standard 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 headers. Xplained Pro MCU boards
have male headers while Xplained Pro extensions have their female counterparts. Note that all pins are not
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
7
always connected. However, all the connected pins follow the defined pin-out described in Table 3-4, “Xplained
Pro Extension Header” on page 8. The extension headers can be used to connect a wide variety of
Xplained Pro extensions to Xplained Pro MCU boards and to access the pins of the target MCU on Xplained
Pro MCU board directly.
Table 3-4. Xplained Pro Extension Header
Pin number Name Description
1 ID Communication line to the ID chip on 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 positive 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 TWI_SDA Data line for two-wire interface. Always implemented, bus
type.
12 TWI_SCL Clock line for two-wire interface. Always implemented, bus
type.
13 USART_RX Receiver line of Universal Synchronous and Asynchronous
serial Receiver and Transmitter.
14 USART_TX Transmitter line of Universal Synchronous and
Asynchronous serial Receiver and Transmitter.
15 SPI_SS_A Slave select for SPI. Should be unique if possible.
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 the 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 for the 3.3V regulated output. To locate the current measurement header, refer to
Figure 1-1, “SAM D21 Xplained Pro Evaluation Kit Overview” on page 4
Table 3-5. Power Header PWR
Pin number PWR header 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)
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
8
Pin number PWR header Pin name Description
4 VCC_P3V3 Regulated 3.3V (output, used as
main power for the kit)
Note
If the board is powered from a battery source it is recommended to use the PWR header. If there
is a power source connected to EDBG USB, the EDBG is activated and it will consume more
power.
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
9
4. Hardware User 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 I/O 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 on page 7. All headers have a
pitch of 2.54 mm.
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
14 [USART_TX] PB08 SERCOM4 PAD[0] UART TX
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
Notes:
1
The SERCOM4 module is shared between EXT1, 2 and 3 UART's, but uses different pins on EXT1 and EXT2/3.
1
1
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]
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
10
Pin on EXT2 SAM D21 pin Function Shared functionality
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
14 [USART_TX] PB10 SERCOM4 PAD[0] UART TX
1
EXT3
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
Notes:
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
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 TC2/WO[0]
8 [PWM(-)] PA13 TC2/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
14 [USART_TX] PB10 SERCOM4 PAD[0] UART TX
3
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
Notes:
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 0-Ohm 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.
4.2 Peripherals
4.2.1 Crystal
The SAM D21 Xplained Pro kit contains one crystals 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
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
11
cutting the strap and adding a resistor across the strap. More information about oscillator allowance and safety
factor can be found in appnote AVR41001.
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
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
1
http://www.atmel.com/images/doc8333.pdf
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
12
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” on page 6.
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” on page 6.
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” on page 6.
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” on page 6.
Table 4-13. GPIO Lines Connected to the EDBG
Pin on SAM D21 Function
PA27 GPIO0
PA28 GPIO1
PA20 GPIO2
PA21 GPIO3
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
13
5. Hardware Revision History and Known Issues
5.1 Identifying Product ID and Revision
The revision and product identifier of Xplained Pro boards can be found in two ways, through Atmel Studio or
by looking at the sticker on the bottom side of the PCB.
By connecting a 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 Kits
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 kit identifier for SAM D21 Xplained Pro is 2130.
5.2 Revision 2
Revision 2 of SAM D21 Xplained Pro is the initial released version.
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
14
6. Document Revision History
Document
Date Comment
revision
42220A 02/2014 Initial document release
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
15
7. 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.
Atmel SAM D21 Xplained Pro [USER GUIDE]
42220A-MCU-02/2014
16
Atmel Corporation 1600 Technology Drive, San Jose, CA 95110 USA T: (+1)(408) 441.0311 F: (+1)(408) 436.4200 | www.atmel.com
© 2014 Atmel Corporation. All rights reserved. / Rev.: 42220A-MCU-02/2014
Atmel®, Atmel logo and combinations thereof, Enabling Unlimited Possibilities®, AVR®, and others are registered trademarks or trademarks of Atmel
Corporation or its subsidiaries. Windows® is a registered trademark of Microsoft Corporation in U.S. and or other countries. ARM®, Cortex® and others is
a registered trademark of ARM Ltd. Other terms and product names may be trademarks of others.
Disclaimer: The information in this document is provided in connection with Atmel products. No license, express or implied, by estoppel or otherwise, to any intellectual property right is granted
by this document or in connection with the sale of Atmel products. EXCEPT AS SET FORTH IN THE ATMEL TERMS AND CONDITIONS OF SALES LOCATED ON THE ATMEL WEBSITE,
ATMEL ASSUMES NO LIABILITY WHATSOEVER AND DISCLAIMS ANY EXPRESS, IMPLIED OR STATUTORY WARRANTY RELATING TO ITS PRODUCTS INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. IN NO EVENT SHALL ATMEL BE LIABLE FOR
ANY DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE, SPECIAL OR INCIDENTAL DAMAGES (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS AND PROFITS, BUSINESS
INTERRUPTION, OR LOSS OF INFORMATION) ARISING OUT OF THE USE OR INABILITY TO USE THIS DOCUMENT, EVEN IF ATMEL HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES. Atmel makes no representations or warranties with respect to the accuracy or completeness of the contents of this document and reserves the right to make changes to
specifications and products descriptions at any time without notice. Atmel does not make any commitment to update the information contained herein. Unless specifically provided otherwise,
Atmel products are not suitable for, and shall not be used in, automotive applications. Atmel products are not intended, authorized, or warranted for use as components in applications intended
to support or sustain life.
Loading...