Microchip Technology SAM-IoT Wx v2 Installation manual

SAM-IoT Wx v2
SAM IoT Wx v2 Hardware User Guide
Preface
Important: This document is applicable to the SAM-IoT WG v2 development board, which is
preconfigured to send data through the Google Cloud™ IoT Core. The SAM-IoT WG v2 development
board can be reconfigured to send data to different cloud service providers.
The SAM-IoT Wx v2 development board is a small and easily expandable demonstration and development platform
for IoT solutions, which is based on the SAM® microcontroller architecture using Wi-Fi® technology. The development
board is designed to demonstrate the design of a typical IoT application which can be simplified by dividing the
problem into these blocks:
•Smart: Represented by the ATSAMD21G18A microcontroller
•Secure: Represented by the ATECC608B secure element
•Connected: Represented by the ATWINC1510 Wi-Fi controller module
The SAM-IoT Wx v2 development board features the following elements:
• The on-board debugger (nEDBG) supplies full programming and debugging support through MPLAB® X IDE.
It also provides access to a serial port interface (serial to USB bridge) and one logic analyzer channel (debug
GPIO).
• The on-board debugger enumerates on the PC as a mass storage interface device for easy drag-and-drop
programming, Wi-Fi configuration, and full access to the microcontroller application Command Line Interface
(CLI).
• A mikroBUS™ socket enables the user to expand the board capabilities with the selection from 1000+
sensor and actuator options offered by MikroElektronika (www.mikroe.com) through a growing portfolio of Click
boards™.
• A light sensor is used to demonstrate the published data.
• Microchip MCP9808 high-accuracy temperature sensor used to demonstrate published data.
• Microchip MCP73871 Li-Ion/Li-Polymer battery charger with power path management.
• Microchip USB2422T USB Hub Controller - USB 2.0 USB Interface to connect the target ATSAMD21G18A MCU
with PC using USB.
•MPLAB® X IDE software to discover, configure, develop, program, and debug Microchip microcontrollers.
The following figure illustrates the SAM-IoT WG v2 development board
© 2022 Microchip Technology Inc.
and its subsidiaries
User Guide DS70005506A-page 1

SAM-IoT Wx v2
© 2022 Microchip Technology Inc.
and its subsidiaries
User Guide DS70005506A-page 2

Table of Contents
Preface...........................................................................................................................................................1
1. Introduction............................................................................................................................................. 4
1.1. Features....................................................................................................................................... 4
1.2. Board Overview............................................................................................................................5
2. Getting Started........................................................................................................................................6
2.1. Quick Start....................................................................................................................................6
2.2. Design Documentation and Relevant Links................................................................................. 6
3. Application User Guide........................................................................................................................... 7
4. Hardware User Guide............................................................................................................................. 8
4.1. On-Board Debugger Overview.....................................................................................................8
4.2. On-Board Debugger Connections..............................................................................................13
4.3. Power......................................................................................................................................... 13
4.4. Components...............................................................................................................................16
5. Regulatory Approval..............................................................................................................................20
5.1. United States..............................................................................................................................20
5.2. Canada.......................................................................................................................................20
5.3. Taiwan........................................................................................................................................ 21
5.4. List of Antenna Types.................................................................................................................21
6. Hardware Revision History....................................................................................................................22
6.1. Identifying Product ID and Revision........................................................................................... 22
7. Appendix............................................................................................................................................... 23
7.1. Schematics...............................................................................................................................0
7.2. Assembly Drawing......................................................................................................................28
7.3. Mechanical Drawings................................................................................................................. 28
7.4. Bill of Materials...........................................................................................................................30
8. Revision History.................................................................................................................................... 32
The Microchip Website.................................................................................................................................33
Product Change Notification Service............................................................................................................33
Customer Support........................................................................................................................................ 33
Microchip Devices Code Protection Feature................................................................................................33
Legal Notice................................................................................................................................................. 33
Trademarks.................................................................................................................................................. 34
Quality Management System....................................................................................................................... 35
Worldwide Sales and Service.......................................................................................................................36
SAM-IoT Wx v2
© 2022 Microchip Technology Inc.
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User Guide DS70005506A-page 3

1. Introduction
1.1 Features
The following are key features of the SAM-IoT WG v2 development board:
•ATSAMD21G18A Arm® Cortex®-M0+ microcontroller
•ATWINC1510 Wi-Fi module
•ATECC608B CryptoAuthentication™ device
• Pre-configured for Microchip accounts with cloud service providers
– Google Cloud IoT Core
• Four user LEDs
• Two mechanical buttons
• TEMT6000 light sensor
•MCP9808 temperature sensor
• mikroBUS socket
• On-board debugger
– Board identification in Microchip MPLAB X IDE
– One green board power and status LED
– Virtual serial port (USBCDC)
– One logic analyzer channels (debug GPIO)
• Supports drag-and-drop feature
• USB and battery powered
•USB2422T USB hub
•MIC33050 Buck regulator
•MCP73871 Li-Ion/Li-Polymer battery charger
• Fixed 3.3V
SAM-IoT Wx v2
Introduction
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User Guide DS70005506A-page 4

1.2 Board Overview
The SAM-IoT Wx v2 development board is a hardware platform used to evaluate and develop IoT solutions with
the Microchip ATSAMD21G18 Arm Cortex-M0+ based Flash microcontroller, ATECC608B secure element, and the
ATWINC1510 Wi-Fi controller module.
The pre-programmed demonstration application publishes data from the on-board light and temperature sensors read
by the ATSAMD21G18A MCU to the cloud (every second). Any data received from the cloud over the subscribed
topic is sent to the virtual serial port and can be displayed in a serial terminal application. The ATWINC1510 needs a
connection to the Wi-Fi network with an internet connection. The ATECC608B is used to authenticate the hardware
with the cloud to uniquely identify every board. The demonstration application source code can be modified to publish
data to a personal cloud account to begin with a custom cloud application.
The following figure shows the key features and pinout of the SAM-IoT Wx v2 development board.
Figure 1-1. SAM-IoT Wx v2 Development Board
Micro USB Port
Power/Status LED
nEDBG onboard Programmer/debugger
High Speed USB HUB Controller
ADC
RESET
SPI CS
SPI SCK
SPI MISO
SPI MOSI
3.3 V
GND
TEMT6000 Light Sensor
ATSAMD21G18A Microcontroller
User Switch 1
ATWINC1510 Module
Timer/PWM
Interrupt
UART Rx
UART Tx
I2C SCL
I2C SDA
5.0 V
ATECC608B Secure Element
User Switch 0 Error Status LED
Data Transfer LED
Cloud Connection Status LED
Wi-Fi Status LED
GND
LiPo Connector
MCP73871 LiPo Charger
MIC33050 Voltage Regulator
Timer/PWM
LiPo Charge Status LED
SAM-IoT Wx v2
Introduction
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User Guide DS70005506A-page 5

2. Getting Started
2.1 Quick Start
Follow these steps to exploring the SAM-IoT Wx v2 development board:
1. Connect the SAM-IoT Wx v2 development board to the computer.
2. Open the CLICK-ME.HTM file on the Curiosity mass storage disk and perform these actions:
a. Download the latest application.hex firmware.
b. Download the Wi-Fi configuration file WIFI.cfg by entering the required Wi-Fi credentials.
3. Drag-and-drop the application .hex file on the Curiosity drive and wait till update completes.
4. Drag-and-drop the WIFI.cfg configuration file on the Curiosity drive.
The development board will connect to the Wi-Fi network and send data to the web site (mentioned in Step 2)
through a cloud provider.
2.2 Design Documentation and Relevant Links
The following list provides links to the relevant documents and software for the SAM-IoT Wx v2 development board.
•MPLAB Data Visualizer : A program used for processing and visualizing data. The MPLAB Data Visualizer can
receive data from various sources, such as serial ports and the on-board debugger’s Data Gateway Interface, as
found on the Curiosity Nano and Xplained Pro boards.
•MPLAB® X IDE : A software program that runs on a PC (Windows®, Mac OS®, Linux®) to develop applications
for Microchip microcontrollers and digital signal controllers. It is called the Integrated Development Environment
(IDE) as it provides a single integrated environment to develop code for embedded microcontrollers.
•Microchip Sample Store: Users can order device samples here.
SAM-IoT Wx v2
Getting Started
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3. Application User Guide
The ATSAMD21G18A microcontroller is mounted on the SAM-IoT Wx v2 development board and is pre-programmed
with an application ready to publish data to a Microchip account with a cloud service provider and subscribe to
data sent from iot.microchip.com through the cloud service provider. The SAM-IoT WG v2 development board
is pre-configured for Google Cloud IoT Core. The data is read from the cloud and presented to the user on
iot.microchip.com.
The latest firmware and application user’s guide are available for download at EV62V87A kit page.
SAM-IoT Wx v2
Application User Guide
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4. Hardware User Guide
4.1 On-Board Debugger Overview
The SAM-IoT Wx v2 development board contains an on-board debugger for programming and debugging. The
on-board debugger is a composite USB device consisting of these interfaces:
• A debugger that can program and debug the ATSAMD21G18A in MPLAB X IDE.
• A mass storage device that allows drag-and-drop programming of the ATSAMD21G18A.
• A virtual serial port (CDC) that is connected to a Universal Asynchronous Receiver/Transmitter (UART) on
the ATSAMD21G18A and provides an easy way to communicate with the target application through terminal
software.
• A Data Gateway Interface (DGI) for code instrumentation with logic analyzer channels (debug GPIO) to visualize
program flow.
The on-board debugger controls a Power and Status LED (marked PS) on the SAM-IoT Wx v2 development board.
The following table shows how the LED is controlled in different operation modes.
Table 4-1. On-Board Debugger Overview
Operation Mode Power and Status LED
Boot Loader mode The LED blinks slowly during power-up.
Power-up The LED is ON.
Normal operation The LED is ON.
Programming Activity indicator: The LED blinks slowly during programming/debugging.
Drag-and-drop programming Success: The LED blinks slowly for 2 seconds.
Failure: The LED blinks rapidly for 2 seconds.
Fault The LED blinks rapidly if a power fault is detected.
Sleep/Off
The LED is OFF.
The on-board debugger is either in Sleep mode or powered-down.
This can occur if the board is externally powered.
Info: Slow blinking is approximately 1 Hz, and rapid blinking is approximately 5 Hz.
4.1.1 Debugger
The on-board debugger on the SAM-IoT Wx v2 development board appears as a mass storage device with a CDC
on the Host computer’s USB subsystem. The debugger supports full-featured programming and debugging of the
ATSAMD21G18A using MPLAB X IDE or other selected third-party IDEs.
Remember: Ensure that the firmware for the debugger is up-to-date. Firmware upgrades are done
automatically when using MPLAB X IDE.
4.1.2 Virtual Serial Port
The virtual serial port (CDC) is a general purpose serial bridge between the Host PC and a target device.
4.1.2.1 Overview
The on-board debugger implements a composite USB device that includes a standard Communications Device Class
(CDC) interface, which appears on the Host as a virtual serial port. The CDC can be used to stream arbitrary data
in both directions between the Host computer and the target: All characters sent through the virtual serial port on the
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Host computer will be transmitted as UART on the CDC TX pin of the debugger, and UART characters captured on
the CDC RX pin of the debugger will be returned to the Host computer through the virtual serial port.
Figure 4-1. CDC Connection
Info: As shown above, the CDC TX pin of the debugger is connected to a UART RX pin on the target for receiving
characters from the Host computer. Similarly, the CDC RX pin of the debugger is connected to a UART TX pin on the
target for transmitting characters to the Host computer.
4.1.2.2 Operating System Support
On Windows machines, the CDC will enumerate as Curiosity Virtual COM Port and appear in the ports section of the
Windows Device Manager. The COM port number can also be found there.
Important: On the older Windows systems, a USB driver is required for CDC. This driver is included in
installations of MPLAB X IDE.
On Linux machines, the CDC will enumerate and appear as /dev/ttyACM#.
Important: The tty* devices belong to the dialout group in Linux, therefore it is necessary to become a
member of that group to have permissions to access the CDC.
On MAC machines, the CDC will enumerate and appear as /dev/tty.usbmodem#. Depending on which terminal
program is used, it will appear in the available list of modems as usbmodem#.
Important: For all operating systems, ensure to use a terminal emulator that supports DTR signaling.
Refer to the Signaling for additional information.
4.1.2.3 Limitations
Not all UART features are implemented in the on-board debugger CDC. The constraints are outlined here:
•Baud rate: Must be in the range of 1200 bps to 500 kbps. Any baud rate outside this range will be set to the
closest limit, without warning. Baud rate can be changed on-the-fly.
•Character format: Only 8-bit characters are supported.
•Parity: Can be odd, even, or none.
•Hardware flow control: Not supported.
•Stop bits: One or two bits are supported.
4.1.2.4 Signaling
During USB enumeration, the Host OS will start both communication and data pipes of the CDC interface. At this
point, it is possible to set and read back the baud rate and other UART parameters of the CDC, but data sending and
receiving will not be enabled.
When a terminal connects on the Host, it must assert the DTR signal. As this is a virtual control signal implemented
on the USB interface, it is not physically present on the board. Asserting the DTR signal from the Host will indicate to
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the on-board debugger that a CDC session is active. The debugger will then enable its level shifters (if available) and
start the CDC data send and receive mechanisms.
Deasserting the DTR signal will not disable the level shifters but will disable the receiver, therefore no further data will
be streamed to the Host. Data packets that are already queued up for sending to the target will continue to be sent
out, but no further data will be accepted.
Remember: Set up the terminal emulator to assert the DTR signal. Without the signal, the on-board
debugger will not send or receive any data through its UART.
Tip: The CDC TX pin of the on-board debugger will not be driven until the CDC interface is enabled
by the Host computer. Also, there are no external pull-up resistors on the CDC lines connecting the
debugger and the target, which means that during power-up, these lines are floating. To avoid any glitches
resulting in unpredictable behavior, such as framing errors, the target device must enable the internal
pull-up resistor on the pin connected to the CDC TX pin of the debugger.
4.1.2.5 Advanced Use
CDC Override Mode
In normal operation, the on-board debugger is a true UART bridge between the Host and the device. However, in
certain use cases, the on-board debugger can override the basic operating mode and use the CDC TX and RX pins
for other purposes.
Dropping a text file into the mass storage drive of the on-board debugger can be used to send characters out of the
CDC TX pin on the debugger. The file name and extension are trivial, but the text file must start with the characters:
CMD:SEND_UART=
The maximum message length is 50 characters. All remaining data in the frame is ignored.
The default baud rate used in this mode is 9600 bps, but if the CDC is already active or has been configured, the
previously used baud rate still applies.
USB-Level Framing Considerations
Sending data from the Host to the CDC can be done byte-wise or in blocks, which will be chunked into 64-byte USB
frames. Each such frame will be queued up for sending to the CDC TX pin of the debugger. Transferring a small
amount of data per frame can be inefficient, particularly at low-baud rates, as the on-board debugger buffers frames
and not bytes. A maximum of four 64-byte frames can be active at any time. The on-board debugger will throttle the
incoming frames accordingly. Sending full 64-byte frames containing data is the most efficient method.
When receiving data on the CDC RX pin of the debugger, the on-board debugger will queue up the incoming bytes
into 64-byte frames, which are sent to the USB queue for transmission to the Host when they are full. Incomplete
frames are also pushed to the USB queue at approximately 100 ms intervals, triggered by USB start-of-frame tokens.
Up to eight 64-byte frames can be active at any time.
If the Host (or the software running on it) fails to receive data fast enough, an overrun will occur. When this happens,
the last-filled buffer frame will be recycled instead of being sent to the USB queue, and a full frame of data will be
lost. To prevent this occurrence, the user must ensure that the CDC data pipe is being read continuously, or the
incoming data rate must be reduced.
4.1.3 Mass Storage Device
The on-board debugger includes a simple mass storage device implementation, which is accessible for read/write
operations through the Host operating system to which it is connected.
The mass storage device provides the following:
• Read access to basic text and HTML files for detailed kit information and support.
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• Write access for programming Intel® HEX formatted files into the memory of the target device.
• Write access for simple text files for utility purposes.
4.1.3.1 Mass Storage Device Implementation
The on-board debugger implements a highly optimized variant of the FAT12 file system that has several limitations,
partly due to the nature of FAT12 itself and optimizations made to fulfill its purpose for its embedded application.
The Curiosity Nano USB device is USB Chapter 9 compliant as a mass storage device but does not, in any way, fulfill
the expectations of a general purpose mass storage device. This behavior is intentional.
When using the Windows operating system, the on-board debugger enumerates as a Curiosity Nano USB Device
that can be found in the disk drives section of the device manager. The Curiosity drive appears in the file manager
and claims the next available drive letter in the system.
The Curiosity drive contains approximately 1 MB of free space. This does not reflect the size of the Flash on the
target device in any way. When programming an Intel HEX file, the binary data are encoded in ASCII with metadata
providing a large overhead, therefore 1 MB is a trivially chosen value for disk size.
It is not possible to format the Curiosity drive. When programming a file to the target, the file name may appear in the
disk directory listing. This is the operating system’s view of the directory, which in reality has not been updated. It is
not possible to read out the file contents. Removing and replugging the board will return the file system to its original
state, but the target will still contain the application that has been previously programmed.
To erase the target device, copy a text file starting with CMD:ERASE onto the disk.
By default, the Curiosity drive contains the following read-only files for generating icons as well as reporting status,
and linking to further information.
•AUTORUN.ICO: Icon file for the Microchip logo.
•AUTORUN.INF: System file required for Windows Explorer to show the icon file.
•CLICK-ME.HTM: Redirect to the SAM-IoT WG v2 web demonstration application.
•KIT-INFO.HTM: Redirect to the development board website.
•KIT-INFO.TXT: Text file containing details about the board’s debugger firmware version, board name, USB
serial number, device, and drag-and-drop support.
•PUBKEY.TXT: Text file containing the public key for data encryption.
•STATUS.TXT: Text file containing the programming status of the board.
Info: The STATUS.TXT file is dynamically updated by the on-board debugger. The contents may be cached by the
OS, and therefore, do not reflect the correct status.
4.1.3.2 Limitations of Drag-and-Drop Programming
The NVM User Row bits included in the hex file will be ignored when using the drag-and-drop programming.
However, the NVM User Row bits can be programed using MPLAB X IDE.
4.1.3.3 Special Commands
Several utility commands are supported by copying text files to the mass storage disk. The file name or extension is
irrelevant as the command handler reacts to content only.
Table 4-2. Special File Commands
Command Content Description
CMD:ERASE Executes a chip erase of the target.
CMD:SEND_UART= Sends a string of characters to the CDC UART. See CDC Override Mode.
CMD:RESET Resets the target device by entering Programming mode and then exiting Programming mode immediately thereafter.
Exact timing can vary according to the programming interface of the target device (debugger firmware v1.16 or latest).
Info: The commands listed above are triggered by the content being sent to the mass storage emulated disk, and
no feedback is provided in the case of either success or failure.
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4.1.4 Data Gateway Interface
Data Gateway Interface (DGI) is a USB interface for transporting raw and timestamped data between the on-board
debugger and Host computer-based visualization tools. MPLAB Data Visualizer is used on the Host computer to
display debug GPIO data. It is available as a plug-in for MPLAB X IDE or as a stand-alone application that can be
used in parallel with MPLAB X IDE.
Although DGI encompasses several physical data interfaces, the SAM-IoT Wx v2 development board implementation
includes a logic analyzer channel: one debug GPIO channel (also known as DGI GPIO).
4.1.4.1 Debug GPIO
Debug GPIO channels are timestamped digital signal lines connecting the target application to a Host computer
visualization application. They are typically used to plot the occurrence of low-frequency events on a time-axis. For
example, when certain application state transitions occur.
The following figure shows the monitoring of the digital state of a mechanical switch connected to a debug GPIO in
MPLAB Data Visualizer.
Figure 4-2. Monitoring Debug GPIO with MPLAB Data Visualizer
Debug GPIO channels are timestamped, therefore the resolution of DGI GPIO events is determined by the resolution
of the DGI timestamp module.
Important: Although bursts of higher-frequency signals can be captured, the useful frequency range of
signals for which debug GPIO can be used is up to about 2 kHz. Attempting to capture signals above this
frequency will result in data saturation and overflow, which may cause the DGI session to abort.
4.1.4.2 Timestamping
DGI sources are timestamped as they are captured by the debugger. The timestamp counter implemented in the
Curiosity Nano debugger increments at 2 MHz frequency, providing a timestamp resolution of a half microsecond.
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4.1.5 USB HID Support
The USB hub enables the PC to communicate with the target SAMD21G18A MCU using the USB HID interface. This
interface helps the PC tool to provision the ECC608B through the SAMD21 MCU.
Figure 4-3. USB Hub
4.2 On-Board Debugger Connections
The following table provides the connections between the target and the debugger section. All connections between
the target and the debugger are tri-stated as long as the debugger is not actively using the interface. There is little
contamination of the signals, hence the pins can be configured to anything the user requires.
For additional information on how to use the capabilities of the on-board debugger, refer to the On-Board Debugger
Overview.
Table 4-3. On-Board Debugger Connections
Debugger Pin ATSAMD21G18 Pin Function Shared Functionality
CDC TX PB02 SERCOM 5 -
CDC RX PB03 SERCOM 5 -
DBG0 PA31 SWDIO -
DBG1 PA30 SWCLK -
DBG2 PA28 DGI GPIO0 -
DBG3 RESETN RESET -
4.3 Power
4.3.1 Power Source
The development board can be powered through the USB port or by a Li-Ion/Li-Polymer battery. The development
board contains one buck converter for generating 3.3V for the debugger, target, and peripherals. The maximum
available current from the USB is limited to 500 mA. The current will be shared between charging the battery (if
connected) and the target application section. The following figure illustrates the power supply details.
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Figure 4-4. Power Supply Block Diagram
4.3.2 Battery Charger
The SAM-IoT Wx v2 development board features an MCP73871 Li-Ion/Li-Polymer charger and JST battery connector
on board. The charger is configured to limit the charge current to 100 mA to prevent the overcharging of small
capacity batteries. The minimum recommended battery capacity is 400 mA. The table below provides the charge
status of the LEDs.
WARNING
The MCP73871 Li-Ion/Li-Polymer charger has a battery charge voltage of 4.2V. Make sure the battery has
the same charge voltage.
Table 4-4. Charge Status LEDs
LEDs Function
Red (charging) The battery is being charged by the USB
Red (discharging) The battery voltage is low. Triggers if the voltage is under 3.1V.
Green Charge complete
Red and Green Timer Fault. The six-hour charge cycle has timed out before the complete charge.
4.3.3 Hardware Modifications
On the bottom side of the SAM-IoT Wx v2 development board there are two cut-straps, as shown in the following
figure, which are intended for current measurements. Do not leave these unconnected as this can lead to the
microcontrollers being powered through the I/O’s.
Figure 4-5. VCC Cut-Straps
The 5V supply to the mikroBUS socket is connected by default. To remove the 5V supply from the socket, desolder
the 0Ω resistor (0402) below the 5V text, as shown in the following figure.
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Figure 4-6. mikroBUS™ 5V Footprint
SAM-IoT Wx v2
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4.4 Components
4.4.1 ATSAMD21G18A
The Microchip SAM D21 is a series of low-power microcontrollers using the 32-bit Arm Cortex-M0+ processor, and
ranges from 32-pins to 64-pins with up to 256-KB Flash and 32-KB SRAM. The SAM D21 operates at a maximum
frequency of 48 MHz and reaches 2.46 CoreMark/MHz. They are designed for simple and intuitive migration with
identical peripheral modules, hex compatible code, identical linear address map, and pin compatible migration paths
between all devices in the product series. All devices include intelligent and flexible peripherals, such as an Event
System for inter-peripheral signaling, support for a capacitive touch button, slider, and wheel user interfaces.
4.4.2 mikroBUS™ Socket
The SAM-IoT Wx v2 development board features a mikroBUS socket for expanding the functionality of the
development board using MikroElektronika Click boards and other mikroBUS add-on boards. The socket is populated
with two 1x8 2.54 mm pitch female headers and is ready to mount add-on boards.
Table 4-5. mikroBUS™ Socket Pinout
mikroBUS™ Socket Pin ATSAMD21G18A Pin Function Shared Functionality
AN PA02 ADC AIN0 -
RST PA03 GPIO -
CS PA06 SERCOM 0 SPI Chip Select -
SCK PA05 SERCOM 0 SPI Clock -
MISO PA07 SERCOM 0 SPI MISO -
MOSI PA04 SERCOM 0 SPI MOSI -
+3.3V - VCC_TARGET (3.3V) -
GND - Ground -
PWM PB23 TCC3 -
INT PB22 GPIO -
RX PA09 SERCOM 2 UART RX -
TX PA08 SERCOM 2 UART TX -
SCL PA17 SERCOM 1 I2C Clock -
SDA PA16 SERCOM 1 I2C Data -
+5V - VCC_MUX (1), MCP73871output -
GND - Ground -
Note:
1. A 0Ω resistor has been soldered to connect the VCC_MUX pin to the mikroBUS socket. If an add-on module
cannot handle 5V on this pin, the 0 Ω resistor must be removed. For additional information, see Hardware
Modifications.
4.4.3 ATWINC1510 Wi-Fi Module
The ATWINC1510 Wi-Fi module is a low-power consumption IEEE® 802.11 b/g/n IoT module, specifically optimized
for low- power IoT applications. The module integrates a Power Amplifier (PA), Low-Noise Amplifier (LNA), switch,
power management, a printed antenna, or a micro co-ax (U.FL) connector for an external antenna resulting in a small
form factor (21.7x14.7x2.1 mm) design. It is interoperable with the 802.11 b/g/n access points of various vendors.
This module provides SPI ports to interface with a Host controller.
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The ATWINC1510 provides internal Flash memory and multiple peripheral interfaces, including UART and SPI. The
only external clock source needed for the ATWINC1510 is the built-in, high-speed crystal, or oscillator (26 MHz). The
ATWINC1510 is available in a QFN package or as a certified module.
The communication interface between the ATSAMD21G18A and ATWINC1510 Wi-Fi module is the SPI, together with
some enabled signals and interrupts. The rest of the connections are left unconnected.
Table 4-6. ATWINC1510 Connections
ATWINC1510 Pin ATSAMD21G18A Pin Function Shared Functionality
4 RESET_N PB10 GPIO -
9 GND - Ground -
10 SPI_CFG - Pulled-up to VCC_WINC -
11 WAKE PA19 GPIO -
12 GND - Ground -
13 IRQN PA18 EIC EXT INT 2 -
15 SPI_MOSI PA12 SERCOM 4 SPI MOSI -
16 SPI_SSN PA14 SERCOM 4 SPI CS -
17 SPI_MISO PA15 SERCOM 4 SPI MISO -
18 SPI_SCK PA13 SERCOM 4 SPI Clock -
20 VBAT - VCC_WINC (3.3V) -
22 CHIP_EN PB11 GPIO -
23 VDDIO - VCC_WINC (3.3V) -
28 GND - Ground -
29 PADDLE - Ground -
SAM-IoT Wx v2
Hardware User Guide
© 2022 Microchip Technology Inc.
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User Guide DS70005506A-page 17

4.4.4 ATECC608B
The ATECC608B is a secure element from the Microchip CryptoAuthentication portfolio with advanced Elliptic
Curve Cryptography (ECC) capabilities. With ECDH and ECDSA being built right in, this device is ideal for the
rapidly growing IoT market by easily supplying the full range of security, such as confidentiality, data integrity,
and authentication to systems with MCU or MPUs running encryption or decryption algorithms. Similar to all
Microchip CryptoAuthentication products, the new ATECC608B employs ultra-secure hardware-based cryptographic
key storage and cryptographic countermeasures which eliminate potential backdoors linked to software weaknesses.
The ATECC608B uses TrustFLEX for TLS-based network secure authentication in addition to many more use
cases. The device comes pre-configured with more use cases than just the device to cloud secure authentication
Trust&GO offer. It offers a pre-architected implementation for accessory authentication, firmware validation, secure
boot assistance, key rotation and more. Compatible for AWS IoT, Microsoft Azure, Google Cloud Platform and any
TLS networks with code examples for WolfSSL, mBedTLS, or CycloneSSL.
The ATECC608B CryptoAuthentication device on the SAM-IoT Wx v2 development board is used to authenticate the
hardware with cloud service providers to uniquely identify every board.
Note: 7-bit I2C address: 0x6C.
Table 4-7. ATECC608B Connections
ATECC608B Pin ATSAMD21G18A Pin Function Shared Functionality
SDA PA22 SERCOM 3 MCP9808
SCL PA23 SERCOM 3 MCP9808
4.4.5 Temperature Sensor
The MCP9808 digital temperature sensor converts temperatures between -20°C and +100°C to a digital word.
Additional features:
• Accuracy:
– ±0.25°C (typical) from -40°C to +125°C
– ±0.5°C (maximum) from -20°C to +100°C
• User Selectable Measurement Resolution:
– 0.5°C, 0.25°C, 0.125°C, 0.0625°C
• User Programmable Temperature Limits:
– Temperature Window Limit
– Critical Temperature Limit
• User Programmable Temperature Alert Output
• Operating Voltage Range:
– 2.7V to 5.5V
• Operating Current:
– 200 μA (typical)
• Shutdown Current:
– 0.1 μA (typical)
The MCP9808 temperature sensor is connected to the ATSAMD21G18A through the I2C and a GPIO for user
configurable alert output.
Note: The 7-bit I2C address is 0x18.
Table 4-8. MCP9808
MCP9808 Pin ATSAMD21G18A Pin Function Shared Functionality
SDA PA22 SERCOM 3 ATECC608B
SCL PA23 SERCOM 3 ATECC608B
Alert PA27 EIC EXT INT15 -
SAM-IoT Wx v2
Hardware User Guide
© 2022 Microchip Technology Inc.
and its subsidiaries
User Guide DS70005506A-page 18

4.4.6 Light Sensor
The TEMT6000X01 light sensor is mounted on the SAM-IoT Wx v2 development board for measuring the light
intensity. The sensor is a current source that will induce a voltage across the series resistor, which in turn can be
measured by the ATSAMD21G18A ADC. The current is exponentially relative to luminance, from about 10 µA @ 20lx
to 50 µA @ 100lx. The series resistor has a value of 10 kΩ.
Table 4-9. ATSAMD21G18A
ATSAMD21G18A Pin Function Shared Functionality
PB08 ADC AIN2 -
4.4.7 LED
Four LEDs are available on the SAM-IoT Wx v2 development board that can be controlled with PWM or GPIO. The
LEDs can be activated by driving the connected I/O line to GND.
Table 4-10. LED Connections
ATSAMD21G18A Pin Function Description
PA10 GPIO Red LED
PA11 GPIO Yellow LED
PA20 GPIO Green LED
PA21 GPIO Blue LED
4.4.8 Mechanical Buttons
The SAM-IoT Wx v2 development board contains two generic user-configurable mechanical buttons. When a button
is pressed, it will drive the connected I/O line to ground (GND).
Info: There are no pull-up resistors connected to the generic user buttons, ensure to enable the internal pull up in
the ATSAMD21G18A to use the buttons.
Table 4-11. Mechanical Buttons
ATSAMD21G18A Pin Description Shared Functionality
PA00 User switch 0 (SW0) -
PA01 User switch 1 (SW1) -
SAM-IoT Wx v2
Hardware User Guide
© 2022 Microchip Technology Inc.
and its subsidiaries
User Guide DS70005506A-page 19

5. Regulatory Approval
5.1 United States
Contains Transmitter Module FCC ID: 2ADHKATWINC1510.
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part
15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a
residential installation. This equipment generates, uses, and can radiate radio frequency energy, and if not installed
and used in accordance with the instructions, may cause harmful interference to radio communications. However,
there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.
5.2 Canada
Contains IC: 20266-ATWINC1510.
This device complies with Industry Canada's license-exempt RSS standards. Operation is subject to the following two
conditions:
1. This device may not cause interference.
2. This device must accept any interference, including interference that may cause undesired operation of the
device.
Le présent appareil est conforme aux CNR d'Industrie Canada applicables aux appareils radio exempts de licence.
L'exploitation est autorisée aux deux conditions suivantes:
1. l'appareil ne doit pas produire de brouillage, et
2. l'utilisateur de l'appareil doit accepter tout brouillage radioélectrique subi, même si le brouillage est susceptible
d'en compromettre le fonctionnement.
Guidelines on Transmitter Antenna for License Exempt Radio Apparatus:
Under Industry Canada regulations, this radio transmitter may only operate using an antenna of a type and maximum
(or lesser) gain approved for the transmitter by Industry Canada. To reduce potential radio interference to other users,
the antenna type and its gain should be so chosen that the equivalent isotropically radiated power (e.i.r.p.) is not
more than that necessary for successful communication.
Conformément à la réglementation d'Industrie Canada, le présent émetteur radio peut fonctionner avec une antenne
d'un type et d'un gain maximal (ou inférieur) approuvé pour l'émetteur par Industrie Canada. Dans le but de réduire
les risques de brouillage radioélectrique à l'intention des autres utilisateurs, il faut choisir le type d'antenne et son
gain de sorte que la puissance isotrope rayonnée équivalente (p.i.r.e.) ne dépasse pas l'intensité nécessaire à
l'établisse-ment d'une communication satisfaisante.
SAM-IoT Wx v2
Regulatory Approval
© 2022 Microchip Technology Inc.
and its subsidiaries
User Guide DS70005506A-page 20