Atmel SAM R21 Xplained Pro User manual

SMART ARM-based Microcontrollers
SAM R21 Xplained Pro
USER GUIDE
Preface
The Atmel® SAM R21 Xplained Pro evaluation kit is a hardware platform to
evaluate the ATSAMR21G18A microcontroller.
Supported by the Atmel Studio integrated development platform, the kit
provides easy access to the features of the Atmel ATSAMR21G18A 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 ATSAMR21G18A.
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................................................................................................................4
1.1. Features....................................................................................................................................... 4
1.2. Kit Overview................................................................................................................................. 4
2. Getting Started...........................................................................................................6
2.1. Xplained Pro Quick Start.............................................................................................................. 6
2.2. Design Documentation and Relevant Links................................................................................. 6
3. Xplained Pro.............................................................................................................. 8
3.1. Embedded Debugger................................................................................................................... 8
3.2. Hardware Identification System....................................................................................................9
3.3. Power Sources............................................................................................................................. 9
3.4. Xplained Pro Headers and Connectors......................................................................................10
3.4.1. Xplained Pro Standard Extension Header................................................................... 10
3.4.2. Xplained Pro Power Header.........................................................................................11
4. Hardware User Guide..............................................................................................12
4.1. Connectors................................................................................................................................. 12
4.1.1. Xplained Pro Extension Headers.................................................................................12
4.1.2. Alternate Signals Header.............................................................................................13
4.1.3. Current Measurement Header..................................................................................... 14
4.1.4. Cortex Debug Connector............................................................................................. 14
4.2. Peripherals................................................................................................................................. 14
4.2.1. Crystal..........................................................................................................................14
4.2.2. Mechanical Buttons..................................................................................................... 15
4.2.3. LED..............................................................................................................................15
4.2.4. USB............................................................................................................................. 15
4.2.5. RF................................................................................................................................ 15
4.3. 1.8V Operation........................................................................................................................... 16
4.4. Embedded Debugger Implementation........................................................................................17
4.4.1. Serial Wire Debug........................................................................................................17
4.4.2. Virtual COM port.......................................................................................................... 18
4.4.3. Atmel Data Gateway Interface.....................................................................................18
5. Kit Specific Data...................................................................................................... 19
6. Agency Certification.................................................................................................20
6.1. United States (FCC)................................................................................................................... 20
6.2. European Union (ETSI).............................................................................................................. 20
6.3. Canada (IC)................................................................................................................................21
6.4. List of Antennas Tested With This Product.................................................................................21
7. Appendix..................................................................................................................23
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7.1. Getting Started with IAR.............................................................................................................23
7.2. Connecting a SAM-ICE to an Xplained Pro Board..................................................................... 26
8. Hardware Revisions and Known Issues.................................................................. 28
8.1. Identifying Product ID and Revision........................................................................................... 28
8.2. Revision 3...................................................................................................................................28
9. Document Revision History..................................................................................... 29
10. Evaluation Board/Kit Important Notice.....................................................................30
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1. Introduction
1.1. Features
•Atmel ATSAMR21G18A microcontroller
•Embedded debugger (EDBG)
–USB interface
–Programming and debugging on board SAM R21 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
–Two extension headers
•Antenna
–One ceramic chip antenna (2450AT18D0100)
–One SMA connector for external antenna
•Three possible power sources
–External power
–Embedded debugger USB
–Target USB
•32kHz crystal
•16MHz crystal
•USB interface, device
1.2. Kit Overview
The Atmel SAM R21 Xplained Pro evaluation kit is a hardware platform to evaluate the Atmel
ATSAMR21G18A.
The kit offers a set of features that enables the ATSAMR21G18A user to get started using the
ATSAMR21G18A 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 R21 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 R21
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 R21 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 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.
•Design Documentation - Package containing CAD source, schematics, BOM, assembly drawings,
3D plots, layer plots, etc.
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•Hardware Users Guide in PDF format - PDF version of this User Guide.
•SAM R21 Xplained Pro at www.atmel.com - www.atmel.com 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 R21 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 ATSAMR21G18A.
On SAM R21 Xplained Pro, the SWD interface is connected between the EDBG and the
ATSAMR21G18A.
The Virtual COM Port is connected to a UART on the ATSAMR21G18A 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 ATSAMR21G18A 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 ATSAMR21G18A. 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
ATSAMR21G18A 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 R21 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 R21 Xplained Pro kit can be powered by several power sources as listed in the table below.
Table 3-3. Power Sources for SAM R21 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 R21 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 User Guide
4.1. Connectors
This chapter describes the implementation of the relevant connectors and headers on SAM R21 Xplained
Pro and their connection to the ATSAMR21G18A. 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 Extension Headers
The SAM R21 Xplained Pro headers EXT1 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 Xplained Pro extension header specification. All headers have a pitch of 2.54mm.
Table 4-1. Extension Header EXT1
Pin on EXT1 SAM R21 pin Function Shared functionality
1 [ID] - Communication line to ID chip
on extension board
2 [GND] - GND
3 [ADC(+)] PA06 AIN[6]
4 [ADC(-)] PA07 AIN[7]
5 [GPIO1] PA13 GPIO
6 [GPIO2] PA28 GPIO
7 [PWM(+)] PA18 TCC0 / WO[2]
8 [PWM(-)] PA19 TCC0 / WO[3]
9 [IRQ/GPIO] PA22 EXTINT[6]
10 [SPI_SS_B/GPIO] PA23 GPIO
11 [TWI_SDA] PA16 SERCOM1 PAD[0] I²C SDA EXT3 and EDBG
12 [TWI_SCL] PA17 SERCOM1 PAD[1] I²C SCL EXT3 and EDBG
13 [USART_RX] PA05 SERCOM0 PAD[1] UART RX EDBG
14 [USART_TX] PA04 SERCOM0 PAD[0] UART TX EDBG
15 [SPI_SS_A] PB03 SERCOM5 PAD[1] SPI SS
16 [SPI_MOSI] PB22 SERCOM5 PAD[2] SPI MOSI EXT3 and EDBG
17 [SPI_MISO] PB02 SERCOM5 PAD[0] SPI MISO EXT3 and EDBG
18 [SPI_SCK] PB23 SERCOM5 PAD[3] SPI SCK EXT3 and EDBG
19 [GND] - GND
20 [VCC] - VCC
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Table 4-2. Extension Header EXT3
Pin on EXT3 SAM R21 pin Function Shared functionality
1 [ID] - Communication line to ID chip
on extension board
2 [GND] - GND
3 [ADC(+)] - -
4 [ADC(-)] - -
5 [GPIO1] PA15 GPIO
6 [GPIO2] -
7 [PWM(+)] -
8 [PWM(-)] -
9 [IRQ/GPIO] -
10 [SPI_SS_B/GPIO] PA08 GPIO EDBG
11 [TWI_SDA] PA16 SERCOM1 PAD[0] I²C SDA EXT1 and EDBG
12 [TWI_SCL] PA17 SERCOM1 PAD[1] I²C SCL EXT1 and EDBG
13 [USART_RX] - -
14 [USART_TX] - -
15 [SPI_SS_A] PA14 GPIO EDBG
16 [SPI_MOSI] PB22 SERCOM5 PAD[2] SPI MOSI EXT1 and EDBG
17 [SPI_MISO] PB02 SERCOM5 PAD[0] SPI MISO EXT1 and EDBG
18 [SPI_SCK] PB23 SERCOM5 PAD[3] SPI SCK EXT1 and EDBG
19 [GND] - GND
20 [VCC] - VCC
Related Links
Xplained Pro Standard Extension Header on page 10
4.1.2. Alternate Signals Header
The alternate signals header is marked with "Alternate" in silkscreen of the kit. The signals provided here
are otherwise hard to do measurements on.
Table 4-3. Alternate Signals Header
Pin on header Pin on SAM R21 Function
1 PA09 RFCTRL1, negative antenna switch control signal
2 PA12 RFCTRL2, positive antenna switch control signal
3 PA27 GPIO, chip select on the EDBG DGI SPI bus
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4.1.3. Current Measurement Header
An angled 1x2, 100mil pin-header marked with MCU current measurement is located at the upper edge of
the SAM R21 Xplained Pro. All power to the ATSAMR21G18A 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
ATSAMR21G18A to be powered through its I/O pins. This may cause permanent damage to the
device.
4.1.4. Cortex Debug Connector
The Cortex® debug connector is provided to enable external debuggers to be connected to the
ATSAMR21G18A. The footprint is made for a 2x5 50mil connector and the pinout is shown in the table
below. This header should only be used when the EDBG is disconnected from the target. For more
information, see 1.8V Operation.
Table 4-4. Cortex Debug Connector
Pin on connector Connected Function
1 VCC Target Voltage reference
2 PA31_SWDIO Debug data
3 GND GND
4 PA30_SWCLK Debug clock
5 GND GND
6 NC -
7 NC -
8 NC -
9 GND GND detect
10 RESETN Target reset
4.2. Peripherals
4.2.1. Crystal
The SAM R21 Xplained Pro kit contains one crystal that can be used as clock source for the SAM R21
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.
Note:
The 16MHz crystal is connected directly to the RF die inside the SAM R21. The clock signal generated by
the crystal is routed from the CLKM pin on the RF die to a GCLK I/O pin on the microcontroller. For more
information on how the RF die is connected to the microcontroller and how to configure the CLKM pin,
see the SAM R21 datasheet.
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Table 4-5. External 32.768kHz Crystal
Pin on SAM R21 Function
PA00 XIN32
PA01 XOUT32
Table 4-6. External 16MHz Crystal
Pin on SAM R21 Function
XTAL1 XIN
XTAL2 XOUT
4.2.2. Mechanical Buttons
SAM R21 Xplained Pro contains two mechanical buttons. One button is the RESET button connected to
the SAM R21 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 4-7. Mechanical Buttons
Pin on SAM R21 Silkscreen text
RESETN RESET
PA28 SW0
4.2.3. LED
There is one yellow LED available on the SAM R21 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 4-8. LED Connections
Pin on SAM R21 LED
PA19 Yellow LED0
4.2.4. USB
The SAM R21 Xplained Pro has a Micro-USB receptable for use with the SAM R21 USB module. To be
able to detect when a USB cable is connected, a GPIO/ADC is used to detect the VBUS voltage on the
connector.
Table 4-9. USB Connections
Pin on SAM R21 USB
PA07 VBUS Detection
PA24 USB D-
PA25 USB D+
4.2.5. RF
The main feature of SAM R21 Xplained Pro is to show the RF capability of the ATSAMR21G18A device.
This device has bidirectional 100Ω differential antenna pins, which are fed through a balun (Johanson
Technology, 2450BM15A0015) to create a single 50Ω unbalanced output/input. This kit has a passive
analog RF switch (Skyworks Solutions Inc, AS222-92LF) connected to the unbalanced output of the
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balun. The switch is driven by the RFCTRL1 and RFCTRL2 pins of the ATSAMR21G18A, which feature
Antenna Diversity to enable the device to automatically select the best signal from two antennas (can also
be selected manually). The output of the switch is connected to a ceramic chip antenna (Johanson
Technology, 2540AT18D0100) and a SMA connector for external antennas.
Table 4-10. RF Connections
Pin on SAM R21 RF Shared functionality
RFP RF balanced output (positive)
RFN RF balanced output (negative)
PA09 / RFCTRL1 RF switch control signal (negative) EDBG
PA12 / RFCTRL2 RF switch control signal (positive) EDBG
4.3. 1.8V Operation
The SAM R21 Xplained Pro board is operated at 3.3V by default, but it also has the possibility of running
at lower voltages from an external supply. The EDBG is designed to run from a 3.3V supply and won't
work on other voltages, therefore all connections from the EDBG and the on board 3.3V regulator to the
ATSAMR21G18A have to be removed. Figure 4-1 1.8V Operation Modifications shows all components
that have to be removed for 1.8V operation.
When the components are removed the kit can be supplied with a desired voltage through the pins
marked 3V3 (pin four) and GND (pin two) on the power header described in Xplained Pro Power Header.
To program and debug the ATSAMR21G18A a 2x5 50mil header has to be mounted above EXT1 as
shown in Figure 1-1 SAM R21 Xplained Pro Evaluation Kit Overview.
Note:
Operating the SAM R21 Xplained Pro on other voltages than 3.3V requires physical modifications on the
kit using a soldering iron and an external debugger for programming the ATSAMR21G18A.
The on board LED is selected for 3.3V operation, the light level at 1.8V operation is very low. To increase
the emitted light level the value of the series resistor can be lowered.
The EDBG functionality can be restored by re-soldering the removed components, they are all 0Ω
resistors.
Important:
The voltage supplied through the power header is applied directly to the ATSAMR21G18A and
the extension headers. Applying a voltage greater than 3.3V may damage the board
permanently.
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Figure 4-1. 1.8V Operation Modifications
4.4. Embedded Debugger Implementation
SAM R21 Xplained Pro contains an Embedded Debugger (EDBG) that can be used to program and
debug the ATSAMR21G18A 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 R21 GPIOs. Atmel Studio can be used as a front end for the Embedded Debugger.
4.4.1. Serial Wire Debug
The Serial Wire Debug (SWD) use two pins to communicate with the target.
Table 4-11. SWD Connections
Pin on SAM R21 Function
PA30 SWD clock
PA31 SWD data
Related Links
Embedded Debugger on page 8
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4.4.2. Virtual COM port
The Embedded Debugger acts as a Virtual Com Port gateway by using one of the ATSAMR21G18A
UARTs.
Table 4-12. Virtual COM Port Connections
Pin on SAM R21 Function
PA04 SERCOM0 PAD[0] UART TXD (SAM R21 TX line)
PA05 SERCOM1 PAD[1] UART RXD (SAM R21 RX line)
Related Links
Embedded Debugger on page 8
4.4.3. Atmel Data Gateway Interface
The Embedded Debugger features an Atmel Data Gateway Interface (DGI) by using either an SPI or I²C
port. The DGI can be used to send a variety of data from the SAM R21 to the host PC.
Table 4-13. DGI Interface Connections When Using SPI
Pin on SAM R21 Function
PA27 GPIO SPI SS (Slave select) (SAM R21 is Master)
PB02 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 4-14. DGI Interface Connections When Using I²C
Pin on SAM R21 Function
PA16 SERCOM1 PAD[0] I²C SDA (Data line)
PA17 SERCOM1 PAD[1] I²C 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 R21
application code.
Table 4-15. GPIO Lines Connected to the EDBG
Pin on SAM R21 Function
PA08 GPIO0
PA09 GPIO1
PA12 GPIO2
PA14 GPIO3
Related Links
Embedded Debugger on page 8
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5. Kit Specific Data
One of the user pages in the EDBG is programmed with data specific to the SAM R21 Xplained Pro. The
data can be read through the I2C interface connected to the EDBG. For detailed information, see the
EDBG User Guide. All data is stored as little endian.
Table 5-1. MAC64Register, Offset: 0x00
Name Description Size [bits]
MAC64 MAC64 Address (hex) 64
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6. Agency Certification
6.1. United States (FCC)
This equipment complies with Part 15 of the FCC rules and regulations. To fulfill FCC Certification
requirements, an OEM manufacturer must comply with the following regulations:
1. This equipment (SAM R21 Xplained Pro) is for use for evaluation purposes only and must not be
incorporated into any other device or system.
Important:
This equipment complies with Part 15 of the FCC Rules. Operation is subject to the following
two conditions: (1) this device may not cause harmful interference, and (2) this device must
accept any interference received, including interference that may cause undesired operation
(FCC 15.19).
The internal / external antenna(s) used for this mobile transmitter must provide a separation distance of at
least 20cm from all persons and must not be colocated or operating in conjunction with any other antenna
or transmitter.
Installers must be provided with antenna installation instructions and transmitter operating conditions for
satisfying RF exposure compliance. This device is approved as a mobile device with respect to RF
exposure compliance, and may only be marketed to OEM installers. Use in portable exposure conditions
(FCC 2.1093) requires separate equipment authorization.
Important:
Modifications not expressly approved by this company could void the user's authority to operate
this equipment (FCC section 15.21).
Important:
This equipment has been tested and found to comply with the limits for a Class A digital device,
pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable
protection against harmful interference when the equipment is operated in a commercial
environment. This equipment generates, uses, and can radiate radio frequency energy and, if
not installed and used in accordance with the instruction manual, may cause harmful
interference to radio communications. Operation of this equipment in a residential area is likely
to cause harmful interference in which case the user will be required to correct the interference
at his own expense (FCC section 15.105).
6.2. European Union (ETSI)
The SAM R21 Xplained Pro Evaluation kits has been certified for use in European Union countries. A
Declaration of Conformity must be issued for each of these standards and kept on file as described in
Annex II of the R&TTE Directive.
Furthermore, the manufacturer must maintain a copy of the modules' documentation and ensure the final
product does not exceed the specified power ratings, antenna specifications, and/or installation
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