Raspberry Pi

The Raspberry Pi lesson index is displayed to the left.

Below are the most recent lessons.

3D Printing: Design – Nametags

Overview In this lesson, you will learn how to create a personal 3D nametag using TinkerCAD Before you start Have an internet connected laptop/desktop Has already created a TinkerCAD account Has familiarity with TinkerCAD controls Mouse (optional) Procedure Starting with an empty workplace, find and place the ‘Box’ object from the right panel to act […]

RPi Node-Red: Push Button+ RGB LED or Buzzer

Parts List: Getting Started: Setting up the Hardware Setting up Node-Red Start Node-Red and navigate to 127.0.0.1:1880.  Drag one Raspberry Pi input node and five Raspberry Pi output nodes into the flow area. Double click on the Raspberry Pi input node to open its configuration menu.  Set the Pin to GPIO25.  Name the node “Button”. […]

RPi Node-Red: PIR + RGB LED or Buzzer

Parts List: Getting Started: Setting up the Hardware Setting up Node-Red Start Node-Red and navigate to 127.0.0.1:1880.  Drag one Raspberry Pi input node and five Raspberry Pi output nodes into the flow area. Double click on the Raspberry Pi input node to open its configuration menu.  Set the Pin to GPIO20.  Name the node “PIR”. […]

RPi Node-Red: RGB LED

Parts List: Getting Started: Setting up the hardware: Setting up on Node-Red: Setting up Out Nodes     Setting up Inject Nodes: Deploy the flow

RPi Node-Red: Push Button

Parts List: What is a Push Button? A push button is a momentarily activated button.  When the button mechanism is fully depressed an internal electrical connection is made and this newly made connection can be read as the activation of the button. Getting Started:   Setting up Node-Red Start Node-Red and navigate to 127.0.0.1:1880.  Drag […]

automatically running node-red, as root

This tutorial shows you how to have node-red start and run as root instead of a normal user. This is necessary for the RGB Matrix node: node-red-contrib-easybotics-led-matrix Open a terminal and paste in the following lines: sudo systemctl enable nodered.service sudo npm config set unsafe-perm true Now Node-Red will start automatically when the Raspberry Pi boots up. The second line tells […]

Selfie station example project

Here is an example of an applied design thinking project done with a class of 17 students at the University of Hawaii Hilo Upward Bound T3 alliance program during the summer of 2018.  Node Red and physical Raspberry Pi setup instructions can be found on this post. Students had mastered the skills associated with basic […]

Setting up Node Red for a Selfie Station

Here is the Node Red setup for a Selfie Station where a button is pushed, a LED light ring turns on, a photo is taken, which is then emailed to a dedicated email.  Its very similar to this project that was done by teams of students at UH Hilo. Step 1.  Set up the light […]

RPi Node-Red Auto Start

When deploying a Raspberry Pi as a permanent/semi permanent installation is will be useful to have Node-Red start persistently, in the case of power failure, etc. Open a terminal and paste the following command sudo systemctl enable nodered.service Now Node-Red will start automatically when the Raspberry Pi boots up.

(Archive) RPi Node-Red: DHT11 Temperature and Humidity Sensor

Please wire up your DHT11 sensor as below: To be able to use the DHT11 temperature and humidity sensor we will have to install the Node-Red node and the BCM2835 library to support it, the easiest way is explained below. First open a terminal  window and copy and paste the entire code block and press enter. […]