KNoT Hardware PCBs

Here you'll find all the design and outputs files of the hardware that supports KNoT platform application software. Since KNoT is an open-source project, the hardware development also follow the best practices suggested by the open source hardware association (OSHWA).

Overview

KNoT project includes three board types:

1. Starter Boards
2. Development Boards
3. Reference Design Boards

Starter Boards

This board offers support for the embedded software development and preliminary hardware evaluation. They're build by the integration of existing modules and are composed of microcontroller, radio and power supply circuit. This boards help popularization of the KNoT Platform because they are cheaper and easier to assembly and distribute to the community.

Development Board

This PCB is self contained and has two goals: (i) to serve as a development platform with embedded firmware for prototypes that can be validated on field and (ii) to serve as baseline for specific hardware development for final products, as schematics and layouts can be rapidly customized to attend to specific demands.

Reference Design

The Reference Design is composed of hardware, firmware and (eventually) desktop/mobile software. They are designed to demonstrate the KNoT platform used in real solutions. A Reference Design can be based on a Starter or Development Board tailored to be used in a specific solution.

Available Boards

The KNoT Platform follows the hub-and-spoke architecture thus comprises of end-nodes, simply called Things, a Gateway to relay the Things messages and cloud applications. Therefore we have two kinds of boards, the Things which are based on Arduino Pro Mini and the Gateway which is based on a Raspberry Pi 3.

KNoT Gateway Starter Board

KNoT Gateway Starter Board consists of a shield board for Raspberry Pi 2 and 3. This shield disposes of:

• 2x8 female header for easily coupling a nRF24L01+ module for wireless communication with the KNoT Things
• 3.3V Low Dropout voltage regulator for more stable power feed
• 1x8 female header for coupling the Itead PN532 NFC card header
• 2x General purpose Push Buttons(with external pull-up resistor circuit and a capacitive high frequency filter)
• 3x General purpose red LEDs
• Prototyping area with 9x16 prototyping holes with 5V, 3V3 and GND connections.

All modules are mapped into the Raspberry Pi pins so no extra jumpers are required to use it, just need to connect the modules. (you can see pins connections in the gateway starter board schematic file). The connection between the shield modules and the Raspberry Pi pins are made by a male/female 2x20 header thats fit in the Raspberry's GPIO header and ease the access to the Raspberry's GPIO.

KNoT Gateway Mini Starter Board 🆕

KNoT Gateway Mini Starter Board consists of a tiny shield board for Raspberry Pi and saves a lot of space and pins, since it only requires 16 pins from the Raspberry Pi 40-pin header. The board supports the nRF24L01+ radio module and also contains:

• 2x user buttons
  • Things Pairing: starts the pairing process to Things nearby
  • Reset: provides a way to reset the gateway firmware to default parameters
• 3x LEDs
  • Power
  • Connection Status
  • Activity

KNoT Thing Starter Board

KNoT Thing Starter Board, currently on it third version (Rev 01.02) is a device board based on Arduino and nRF24L01+ radio. The board supports the composition of an Arduino Pro Mini 5V 16MHz, a nRF24L01+ 2.4GHz module and a FTDI FL232 Module. The board also provides the KNoT Status LED and a Reset EEPROM button.

In addition, the board brings an user LED, connected to Arduinos PD5 pin. All the Arduino Pins are available on external headers where user can debug their applications or connect external devices, such as sensors or actuators.

All the board components are plated-through hole technology which makes it easy to manually assembly.

There is also a previous version of this board (Rev 01.00) available online on the Upverter E-CAD: Thing Starter Board.

KNoT Thing Development Board

KNoT Thing Development Board consists of an Arduino based PCB with the ATMega328 microcontroler, nRF24L01+ circuit, headers for SPI and I²C communication, push button and status led.

Characteristics

• Supports KNoT version 01.00
• Compatible with Arduino IDE
• Supplied via Micro-USB connector
• nRF24L01+ radio with external antenna
• ATMega328-AU Micro-controller
• Programmed through FTDI232RL USB-Serial converter

KNoT Thing DevBoard PCBs are compatible with the Arduino IDE and may be integrated with peripherals through expansion connectors. Before using the PCB, it's important to burn the bootloader to the Atmega328 micro-controller. For this PCB, the Arduino Pro Mini 3.3V 8MHz bootloader is used (ATmegaBOOT_168_atmega328_pro_8MHz.hex). The use of ICSP is recommended for burning the bootloader via the 3x2 header with SPI interface using an Atmel SPI Programmer and Atmel Studio. Besides burning the bootloader, the ATMega328 fuses also need to be programmed via ICSP with the values:

• Extended: 0xFD
• High: 0xDA
• Low: 0xFF

Development tools

The ECAD tool used is Altium Designer versions 14.2.3 and 14.2.4.

PCB Files

Each PCB project includes the design files:

• Components Library
• Schematics
• Board Layout

The generated output files are:

• Bill Of Materials (BOM)
• Gerber
• NC Drill
• PCAD Netlist
• Assembly Drawing
• Composite Drawing
• Pick and Place
• Schematics (PDF)