Ottawa PC Users Group Microcontrollers



Common microcontrollers:

Some examples:

I am going to discuss the esp8266 and esp32-Cam

Why I like the ESPs

What is it: 

Esp Chip and antenna, ESP8266 Development board, ESP32 - Cam board with camera

Thanks to for the above images.

More information

Internet of things IOT Data

I like to measure things.  Temperature, pressure, moisture, flow, ...

I really like the ESP8266 and ESP32 as I can stick them in zip lock bags all over the place and they measure and in some cases control.

What to do with the data they gather.  I  like to create my own but there are platforms already built.  I either use node red or create a web server in the ESPs  or both.  More later.

Hello World

Or, the micro controller equivalent - flash a LED

We actually have two leds.  One on the ESP8266 Development Board and the external led on the red breadboard.

Code Hello World

// micro controller hello world with 2 leds

// Global variables here
int boardLed = 2;
int externalLed = 5;

// Executed once
void setup() {
    pinMode(boardLed, OUTPUT);
    pinMode(externalLed, OUTPUT);

// Executed Continuously
void loop() {
  digitalWrite(boardLed, HIGH);
  digitalWrite(externalLed, HIGH);
  Serial.println("board led off");
  digitalWrite(boardLed, LOW);
  digitalWrite(externalLed, LOW);
  Serial.println("board led on");

And by request - A comparison to the new Raspberry Pi Pico.

Temperature pressure example

ESP8266 Lolin development board under back deck in its ziplock bag.
The barometric pressure sensor is under the 8266.  The DS18B20 temperature
sensor is the black wire on the left.  It sensor part is about a meter away
where rain and sun don't effect it but there is good air flow.

BMP280 and DS18B20

Code Temperature and Barometric Pressure

Power Control


Detailed Presentation on RF Switches:

Fun Examples - or Silly


Code Social Distancing Hat


Code Addressable Leds

Node Red and collection.

Status Displays.

Each one of the following displays is fed by an ESP8266 with different types of sensors.

The pond has 2 DS18B20 temperature sensors and a flow sensor on the
make up water.  There is an independent level sensor (float switch) that adds
water if the level drops.  The flow sensor ensures that it can only add a
specified amount in a period of time as sometimes the flow switch sticks.

Green House

The on off times are watering intervals.  There is no closed loop control.  The watering
intervals are set manually.


Again no closed loop control.  The fall alarm will warn us if the temperature starts
falling.  This will happen if the cone sitter trips and sometimes it trips sooner than
we would like.  Then it can be overridden.


The temperature by the thermostat.  Some day I will replace the thermostat.

esp32cam camera


A picture of me - thinking                                    Also thinking


My messy office                                     The kiln.  It's not on fire inside about 1000C

This one is a portable. 


This watches my deck.                                    Said deck.

External Platforms

Internet of things IOT  - I like my own but and Node-Red:

-- 2021-02-09 --