Embedded Computing
  • About
  • Blog
  • Hardware
    • Which Platform?
    • Controller Platforms >
      • Adafruit Platform
      • Arduino Plaform
      • BBC micro:bit
      • Espressif Platform
      • iLabs Platform
      • Raspberry Pi Platform (MCU)
      • Seeed Platform
      • Silicon Labs Platform
      • Teensy Plaform
    • Computer Platforms >
      • BeagleBone Platform
      • Raspberry Pi Platform (SBC)
      • UDOO Platform
    • Peripherals >
      • Shields
      • Grove System
      • Sensors
      • Actuators
    • Displays >
      • E-Paper Displays
      • Reflective Displays
      • TFT Displays
      • LCD Displays
    • Legacy Platforms >
      • chipKIT Plaform
      • 4D Systems Platform
      • Intel Platform
      • LaunchPad Plaform
      • BoosterPacks for LaunchPads
      • LightBlue Bean
      • Maple Plaform
      • Mediatek Platform
      • Microsoft Azure IoT DevKit
      • Particle Platform
  • Software
    • Exploring RTOS with Galaxia >
      • Event Library
      • Semaphore Library
      • Mailbox Library
      • Timer Library
      • Clock Library
      • SWI Library
      • Task Library
    • Ultra-Low Power with EnergyTrace >
      • Ultra-Low Power with MSP430
      • Ultra-Low Power with Energia MT and Galaxia
    • Using Integers Instead of Reals
    • Going Python?
  • IoT
    • IoT Platforms: Which Hardware? >
      • Matter with Silicon Labs MG24
    • IoT Services: Which Solution? >
      • Recommended IoT Solutions
      • Platform-Specific IoT Solutions
      • Other IoT Solutions
      • Not tested IoT Solutions
      • Notification Solutions
    • Get Date and Time from Internet with NTP
    • Fast and Easy WiFi Connection with QR-Code
  • Tools
    • How to Start?
    • Reference >
      • Asking for Help
      • Boards Pins Maps
      • Ruler
      • Boards and Plugs
      • I²C Logic Level Converter
      • Standards for Connectors
    • Training >
      • Texas Instruments Workshops
      • Embedded Systems: Shape The World — MOOC edX UTAustinX UT.6.02x
      • Embedded Systems - Shape The World: Microcontroller Input/Output — MOOC edX UTAustinX UT.6.10x
      • Embedded Systems - Shape The World: Multi-Threaded Interfacing — MOOC edX UTAustinX UT.6.20x
      • Real-Time Bluetooth Networks: Shape the World — MOOC edX UTAustinX UT.RTBN.12.01x
      • Systems Thinking with Texas Instruments Robotics System Learning Kit
    • Books >
      • Getting Started with the MSP430 LaunchPad
      • Getting Started with Arduino
      • Arduino Cookbook
    • IDE >
      • The Battle of IDEs
      • More Options
      • Assessing the Next Generation of IDEs
      • Tools for Documentation
    • Equipment >
      • Saleae Logic Analyser
      • Rigol DS1102E Oscilloscope
      • XDS110 Debug Probe with EnergyTrace​
      • Segger J-Link Programmer-Debugger
      • Nordic Power Profiler Kit II
  • Projects
    • Libraries >
      • Master I²C Software Library
      • Date and Time Library
      • highView Library Suite
      • Others Libraries
    • smartDevices >
      • I²C smartColours Smart Sensor
      • I²C smartRFID Smart Sensor
      • I²C smartLED Display
      • I²C smartControls Smart Device
      • I²C smartWiFi Smart Device
      • I²C smartBLE Smart Device
      • I²C smartNode Smart Device
    • IoT Projects >
      • Remote E-Paper Weather and Message Board
      • Typie-Walkie with LoRa and E-Paper Screen
      • Typie-Walkie with E-Paper Screen
      • Remote e-Paper Pictures Panel
      • Remote e-Paper Messages Panel
      • Industrial IoT Project
      • Remote Contactless Temperature Monitor
      • Using Node-RED for IIoT
      • Low Power Home Network Weather Monitoring
      • Updated Low Power Home Network Weather Monitoring
      • Weather and Security Station with Blynk
      • SensorTag to Blynk Using Node-RED
      • Pervasive Reporting
    • AI Projects >
      • Colour Recognition with Neural Network
    • Other Projects >
      • Air Quality Monitoring
      • Driving a Large E-Paper Display with a Compact Xiao RP2040
      • Low-Power E-Paper Weather Station
      • Portable Particulate​ Matter Monitor
      • FRAM-based E-Paper Screen Controller
      • General Purpose 3.5" Screen
      • Colour Recognition with Neural Network
      • A Low Power Weather Station
      • Digital Volt-Amp-Watt Meter
      • Mobile Measurement with LCD Display
      • Screen with SRAM for GUI
      • Volt-Amp-Watt-Meter for Grove
      • Multi-Touch Project with CapTIvate

Xiao Expansion Board

The Xiao Expansion Board is the perfect accessory for the Xiao board.

The board was designed in a very interesting way. Early July 2020, SeeedStudio asked the users to exchange ideas on the #Conceptual Design# Premier Expansion Board for Seeeduino XIAO - Grove XIAO thread. After various iterations on features and form factors, the board was available late November 2020.

The board was sampled by SeeedStudio.
Picture
​The SWD signals are rerouted from the Xiao board through pogo-pins to standard connectors. 

They include SWDIO, SWCLK, RESET and GROUND.
Picture
The Xiao Expansion Board exposes the I²C bus and a Serial port, plus one analog input and one digital GPIO, with standard Grove connectors.

The board also features a battery-backed RTC (I²C), a micro SD-card slot (SPI), a battery circuit for charging, a buzzer and a 128x64 OLED screen  (I²C).

The battery-backed RTC is based on the NXP PCF8563 with a CR1220 coin-cell battery as back-up. Also included, a power management circuit with a switch and a connector for a LiPo battery.

The 128x64 OLED screen is driven by the popular SSD1306 controller and is supported by the LCD_screen Library Suite. Although small, the screen is bright and crisp.
Picture

Pins map

Here is a pins map with the standard colours. The Wiki page provides another one.
Picture

Debugging

The board exposes the SWD signals SWDIO and SWCLK, plus Ground and 3.3V for VTref, and also TX and RX from Serial1. The Segger J-Link programmer-debugger supplies +5V to power the board. 

Just connect the Segger J-Link programmer-debugger with female-female cables (except a female-male for +5V) and install the Segger J-Link software to start debugging.

The Segger J-Link programmer-debugger reroutes the Serial port (here Serial1 on pins 6 and 7) to the USB.
Picture
When using the command-line J-Link utilities, the three terminal windows show, from left to right:
  • The J-Link driver acting as a GDB server 
  • The GDB client, for interactions, 
  • The serial console.

Click to enlarge
Picture
Picture
Picture
The same configuration is here debugged with Ozone, a GUI debugger.

Ozone only needs the .elf fine to start debugging.

The tests shown here were performed with embedXcode, embedded computing on Xcode.
Picture

Conclusion

The unique combination of RTC, screen, micro SD-card slot, battery management and 4 Grove connectors makes the Xiao Expansion Board a perfect choice for data acquisition. The SAMD21 of the Xiao M0 offers plenty of memory and processing power.

​The Xiao Expansion Board is priced at less than USD15 and, combined with the Xiao M0, totals less than USD20, a highly competitive price for a versatile solution.

​The only limitation is the absence of the standard 2x5 0.05" SWD fool-proof connector, which means it can't be used with the affordable Segger J-Link Edu mini programmer-debugger and requires a Segger J-Link Edu instead.
​
The $5 programmer-debugger provides an elegant solution. Hint: it features a Xiao board!
Picture

Pros

  • Powerful and affordable board
  • ​Pogo-pins for SWD debugging

Cons

  • Non-standard 2x5 0.05" SWD fool-proof connector

Wrap-Up

  • Great value
  • Perfect tool to learn debugging

Links

  • Seeed Studio website
  • Product page
  • Wiki page
  • Segger website
Picture

Posted: 12 Dec 2020
​Edited: 18 Dec 2020
Powered by Create your own unique website with customizable templates.