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How to use the Raspberry Pi Imager to download an Operating System to an SD card ready to use with your Raspberry Pi

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This is quick post to show how you can choose and write an Operating System to a SD card for use on a Raspberry PI computer.

Raspberry PI

A Raspberry Pi is a wonderful 5V mini computer that you can use in IoT projects, Programming, Retro Gaming  or as a desktop replacement.

View all Raspberry Pi computers here: https://www.raspberrypi.org/products/

All Raspberry Pi Boards at https://www.raspberrypi.org/products/

The Raspberry Pi has an official Operating system called Raspian.

Raspian LOgo

Many other 3rd party Operations system exist

all 3rd party operating systems

Raspian comes with a Windows like desktop that you can use.

Raspberry PI Desktop

You can even install a Retro Pi image to allow you to play old arcade and Console games in an emulator.

Raspberry Pi Zero W

For this post I will be using the older Raspberry Pi Zero W to setup an operating system.

Raspberry Pi Zero W with all plugs plugged in

I have a few Raspberry PI Zero W’s  (v1.1) laying around

Closer look at one of them

Raspberry Pi Zero W with all plugs plugged in (angle 2)

It’s only has 1x CPU  Core and 512MB of memory. It had Micro USM keyboard and power in plugs.

Micro USB PLugs

I have added a small eBay heat sink to the CPU to help limit thermal throttling when the CPU is working hard.

CPU Heatsink Attached

The good thing about the Raspberry Pi is you can add a fan from the supplied 5V pin.  Read more about available pin’s here: https://raspberrypi.stackexchange.com/questions/83610/gpio-pinout-orientation-raspberypi-zero-w or here https://www.raspberrypi.org/documentation/usage/gpio/

Raspberry Pi Fan

Obviously I would mount it better than this when I turn it on.

You can buy inexpensive drop on references boards to help remind ytou of each pin.

Pi Pin Reference board

The reference board just pops over the pins

Pi reference board

Please visit this page to compare all Raspberry Pi Model Specifications: https://en.wikipedia.org/wiki/Raspberry_Pi#Specifications

Raspberry Pi Specs

SD Card (Required)

The Raspberry Pi does not have a Hard Drive (Magnetic, SSD or NVME) and you will need a Micro SD card. An operating system will need to be written to the SD card and inserted into the MicroSD slot on the Raspberry Pi.

Raspberry Pi Micro SD Slot

I would not put a cheap/slow MicroSD card in the Raspberry PI, aim for a UHS (1) or UHS (3) speed SD card for best bang for buck.

SD card speeds https://www.sdcard.org/developers/overview/speed_class/

Make sure you SD card is not write protected (if it is inserted into an old SD card adapter). My computer does not have a MicroSD card slot.

I have 2x SD card adopters that my MicroSD card inserts into.  Then the SD card inserts into my PC.

Make sure the write lock is not on.

SD Card write lock

SD Image Writing Software

I want to setup a new Pi for use as a PiHole Ad Blocker on  my home network.

https://pi-hole.net/ Screenhshot

I can see the PiHole software needs Rasbian Operating System on the Raspberry Pi (ARM CPU)

Pi Hope Supported OS page

Now that I know what Operating System I need to install I need to grab the SD Imager software from https://www.raspberrypi.org/downloads/

I downloaded the software and open it to install it.

I clicked Install

Raspberri PI Imager install screen

I clicked Next

After the software was installed I clicked Finish to open the software

In the background I formatted (as FAT32)  my 32GB MicroSD Card (that was in the SD card adapter).

I will not do a quick format so every sector on the card is tested and formatted.

Windows Format screen

This may take 30 minutes to format buy it is worth while.  I don’t want a bad SD card making its way to the Raspberry PI.

Windows format in progress.

Format comlplete

Format complete

Open the Raspberry Pi Imager program that you installed earlier.

I clicked “CHOOSE OS“

Raspberry Pi Imager Program

I can choose an operating system to download and write to the SD card

Imager Operating system choices

I chose “Raspian (other)” then “Raspian Full“

Raspian Full Install

Raspian is now the selected operating system

Raspian Selected

I clicked “CHOOSE SD CARD” and selected my 32GB SD card.

Choose SD card dialog

The Operating System and SD Card have been selected

OS and SD card selected

I clicked “WRITE” and within 5 seconds noticed my WiFi was download  the Operating System, Nice.

Raspian Full Downloading via WIFI and writing to the SD card.

The write process will take at least 30 minutes (depending on your internet speed).

The Imager is verifying the SD card

When it’s complete a Verify will be performed and hopefully will have a SD card ready for use in a Raspberry Pi computer.

The write completed and files are on the SD card.

Write Verify Complete

I can now use this SD card in my Raspberry Pi and boot from it to setup the Operating System.

I will prepare 3x MicroSD cards I have ready for My PiHole adventures. Blog post coming.

Setting up a Raspberry Pi Zero W

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fyi: Here is my guide that I created while I set up a Raspberry Pi Zero W. My previous Raspberry PI 2 Setup Guide here and I wanted to try the single-core Raspberry Pi Zero W. Eventually, want to run my Raspberry Pi from batteries (my older guide here).

I plugged in a  2Amp 5v micro USB powder pack, micro HDMI cable, micro USB keyboard and expected to see a light but nothing.  This guide says the Raspberry Pi has no power LED. Unfortunately, I thought the power pack was faulty and I plugged it in a few times and corrupted the installed SD-card.

Failed Setup

After reading this guide I remembered I forgot to switch the monitor to the HDMI input (oops).

Yep, I realized I corrupted the OS on the SD Card.

Old Noobs Operating System

I checked the SD-Card (that I purchased from eBay) I noticed the SD-Card had an older NOOBS 2.0.0 installation in an in an invalid subfolder (that’s why it would not boot).

I plugged the Micro SD card into an SD-Card adapter and plugged it into my Mac (time to install a newer OS).

Downloading the latest Raspian Operating System

I visited https://www.raspberrypi.org/downloads/raspbian/ and download raspbian

I downloaded a 1.66GB Zip File.

The file took 30 mins to download.

I expanded the zip file to a 4.66 img file.

Formatting the SD-Card

I formatted my SD Card with the SD Card Association SD formatting tool from https://www.sdcard.org/downloads/formatter_4/ here.

Setting up the SD-Card

The Raspberry Pi Foundation has a great guide on how to install the Raspberry Pi Raspian image onto an SD-Card here.

I downloaded the free 64MB Etcher program for Mac OS here https://etcher.io/ in order to copy (flash) Raspian onto the SD-Card.

I opened Etcher and selected the Raspian Jesse image file and clicked flash.

The flash will take between 5-10 minutes.

SD Card Contents

The Raspian image is now ready for reinsertion back into the Raspberry Pi to setup

1st Raspberry Pi (Raspian) boot.

The raspberry pi does, in fact, have a  power/activity led with the latest operating system 🙂

The desktop loaded quite swiftly too. My Bay special keyboard detected just fine. You can manually connect to your wifi by entering the following command in the terminal (thanks to this guide).

Pi

Generic Config

I am not using the desktop much so I am happy setting 16MB for the video card.

Get the Mac Address and set a static IP Address (to allow remote SSH management)

After a reboot, I was logged into a shell and was able to bring up the devices network details (including mac address).

Test the network connection

I was successful;y able to ping a remote server via wifi.

Pi Zero Network Update

Static IP Address

Todo: I set up my local ADSL router to give the Raspberry Pi a Static (known) IP every time it boots.

Update the Pi Software (after the network is up)

Now that I knew the network is working I was able to update the Pi software.

Pi Zero

I re-ran the update just in case. Now my Pi is all up to date.

Installed Misc Software

More on setting up an NGINX web server here.

Set the Pi Mouse (regular sized USB devices)

I had small micro USB to larger USB adapters (from eBay)  but could only use a keyboard or mouse at any one time. I Also had a micro USB to multiple micro USB and Ethernet adapter (from eBay) (SN: YS-LAN38) but it failed to work with NOOBS 2.0.0 (maybe it will work with Raspian latest)

I wanted to test regular devices in the case of an emergency.

Pi Zer UBS Adapter

And the mouse works (and the X desktop worked with 16MB assigned)

Help

40 Useful Raspberry Pi Commands.

Todo

Add information on adding and using a 5MP Raspberry Pi camera and setting this up as a https://fearby.com/article/raspberry-pi-2b-security-webcam/secuerity webcam.

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v1.2 DRAFT: Added more images

NodeMCU Introduction – Open source IoT platform based on the ESP8266 Wi-Fi SoC

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Below is a quick review of the NodeMCU v1.0 Dev Kit board microcontroller that can be picked up for under $10. NodeMCU is an open-source IoT platform based on the ESP8266 Wi-Fi SoC.

Specs:

nodemcu003

I ordered 1x Node MCU v1.0 with Free delivery from eBay seller 19star-au for $10.94.

nodemcu001

I have played with Arduinos and having Wifi in a small microcontroller by default is appealing.

How to program your NodeMCU

  1. Goto www.arduino.cc and download the Arduino IDE (1.8.x or higher).
  2. Open the Arduino IDE and find the Preferences Menu
  3. Paste the following in the “Additional Boards Manager” textbbox: http://arduino.esp8266.com/stable/package_esp8266com_index.json
  4. Goto Tools, Boards*, Boards manager and search for “esp8266” and install it.nodemcu002
  5. Close your Arduino IDE and reopen it.
  6. Now choose your board type in the Arduino IDE (Tools, Board, Node MCU, 1.0 ESP-12E..)

You will not be able to select a sample script (e.g Blink) by navigating to File, Examples, ESP8266, Blink.

The Blink code will look like this:

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);     // Initialize the LED_BUILTIN pin as an output
}

// the loop function runs over and over again forever
void loop() {
  digitalWrite(LED_BUILTIN, LOW);   // Turn the LED on (Note that LOW is the voltage level
                                    // but actually the LED is on; this is because 
                                    // it is active low on the ESP-01)
  delay(1000);                      // Wait for a second
  digitalWrite(LED_BUILTIN, HIGH);  // Turn the LED off by making the voltage HIGH
  delay(2000);                      // Wait for two seconds (to demonstrate the active low LED)
}

You can now plug the ESP8266 in and try compile and upload the new sketch to the device.

Mac Troubleshooting: If the Arduino IDE says you do not have a serial port you may need to download the USB-Serial driver from silabs.

If all goes well you will have a blinking light on your ESP8266.

nodemcu004

Now lets try the web server sketch

#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#include <ESP8266mDNS.h>

const char* ssid = "yourwifinetwork";
const char* password = "yourwifipassword";

ESP8266WebServer server(80);

const int led = 13;

void handleRoot() {
  digitalWrite(led, 1);
  server.send(200, "text/plain", "hello from esp8266!");
  digitalWrite(led, 0);
}

void handleNotFound(){
  digitalWrite(led, 1);
  String message = "File Not Found\n\n";
  message += "URI: ";
  message += server.uri();
  message += "\nMethod: ";
  message += (server.method() == HTTP_GET)?"GET":"POST";
  message += "\nArguments: ";
  message += server.args();
  message += "\n";
  for (uint8_t i=0; i<server.args(); i++){
    message += " " + server.argName(i) + ": " + server.arg(i) + "\n";
  }
  server.send(404, "text/plain", message);
  digitalWrite(led, 0);
}

void setup(void){
  pinMode(led, OUTPUT);
  digitalWrite(led, 0);
  Serial.begin(115200);
  WiFi.begin(ssid, password);
  Serial.println("");

  // Wait for connection
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("Connected to ");
  Serial.println(ssid);
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());

  if (MDNS.begin("esp8266")) {
    Serial.println("MDNS responder started");
  }

  server.on("/", handleRoot);

  server.on("/inline", [](){
    server.send(200, "text/plain", "this works as well");
  });

  server.onNotFound(handleNotFound);

  server.begin();
  Serial.println("HTTP server started");
}

void loop(void){
  server.handleClient();
}

A quick check of my routers DHCP list and I found the ESP8266 listening for web requests at 192.168.1.110.

nodemcu005

More to come….

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