Lab Session 1: Intro to microcontrollers programming

Estimated time: 1.5h (1 session)

1. Prepare the Arduino IDE

Follow the installation steps described in this guide.

1. Install Arduino IDE: Download it from this link.

2. Install the M5Stack board family:

   

   You need to copy/paste this text to download the board package

   https://static-cdn.m5stack.com/resource/arduino/package_m5stack_index.json 
   

   

   Once the board package address is set, you can install it from the boards manager.

   Info

   This process may take a few minutes.

   Once installed, you can select M5Core2 from the board selection menu.

   

3. Install the Arduino libraries for M5Core2:

   

   Warning

   When you press Install, you'll see the list of dependencies. You MUST install all the dependencies too.

   Info

   This is a long process that may take several minutes. Be patient...

   Tip

   In case the list of dependencies is that large that you cannot see the Install All button, you can press the tab key Tab twice to put the cursor over the button and then press Enter to install all the dependencies

4. Install the CP2104 driver (USB driver):

   Download it from this link if you're using Windows, from this link if you're using MacOS, or from this other link if you're using Linux.

   More info about USB driver installation here.

   Now, when you connect the M5Core2 devide to the PC with the USB cable, you can select the port in the Arduino IDE.

   

   Info

   • In windows, the port is called COMX, where X is a number that can vary from time to time, e.g., COM5.
   • In linux, the port is called "ttyUSBX" or "ttyACMX", where X is a number that can vary from time to time, e.g., ttyUSB2.

5. Compile and upload the hello_world.ino example from M5Core2 library:

   

   You can press the Upload (in red) button to compile and load the program to the device. Note that the button on the left (Verify - in green) compiles the program but doesn't upload it to the device.

   

6. OPTIONAL (do it ONLY if you have finished all the exercises of the lab session): You can open other examples if you want to see the potential of M5Core2. You can try this one:

   

Additional resources

Here you can find more documentation about some of the basic functions of M5Core2.

Pinout and Important Notes Below is the M5Core2 pinout. The pins marked in red are the ones we will use in the exercises.

Warning

• Some pins on the M5Core2 are preconfigured, so pay attention when connecting external components.
• The ESP32 inside the M5Core2 has 3 serial ports:
  • Serial1 is reserved for the display (do not use it).
  • Serial0 can be configured (pins G3 – RXD0 and G1 – TXD0), but it is reserved for USB connection to the PC.
  • Serial2 is free and can be configured (pins G13 – RXD2 and G14 – TXD2) as regular GPIO using pinMode().

2. Turn an LED ON and OFF

Connect an LED as follows:

Run the following program:

#include <M5Core2.h>
#define LED_PIN 14

void setup() {
  M5.begin(); // Initialize M5Core2
  pinMode(LED_PIN, OUTPUT);
}

void loop() {
  digitalWrite(LED_PIN, HIGH);
  delay(500);
  digitalWrite(LED_PIN, LOW);
  delay(500);
}

Question

Note that you had to include the #include <M5Core2.h> and the M5.begin(); // Initialize M5Core Why did you have to do that? what are these instructions for?

3. Additional exercises

3.1. Blink at a certain frequency

• Using the same circuit as in the previous exercise, write a script that Blinks the LED at a frequency of 10Hz.

  Question

  • For how long does the LED has to be ON or OFF in each cycle?

3.2. Blink and stop

• Using the same circuit as in the previous exercise, write a script that Blinks the LED at a frequency of 2Hz and stops the blinking after 5 seconds.

  Question

  • How many times does the LED blink?
  • What is the final state of the LED when the blink stops, does it remain ON or OFF?

  Tip

  You may need to use the for loop, or the if...else condition.