February 3, 2025

First, in this course, we will create an “LED bracelet.”

At this stage, we are not yet sure what the LED bracelet will look like. We will decide on its design as we go along.

In any case, we will assume that LEDs will be used.

Let’s imagine that we had a strong feeling: “Jewelry with lights will sell!” From this idea, we start to think about how to make a product that will sell.

At the same time, we will make a simple prototype of the circuits and software needed to connect a PC or smartphone to LEDs controlled by a microcontroller.

It may be difficult, but let’s try our best!

...

First, since we cannot do anything unless we can make it, we will start by learning the basics of using a microcontroller.

We will use the following two types of microcontrollers:

• MSP430 series (16-bit microcontroller by TI)

• MSPM0 series (32-bit microcontroller by TI)

There are many types of microcontrollers.

However, all microcontrollers work in a similar way.

This means that if you learn to use one type, you can relatively easily use other types as well.

Let's start by using the MSPM0 series microcontroller.

The reason for choosing this microcontroller is that it is very inexpensive.

There is also a super small version available.

Because it is very small, it can be built into almost anything.

It is small, you know. If you have even a little space, you can likely include it there.

How inexpensive is it? The cheapest type costs only $0.166 per piece when you buy 1,000 units.

Moving on, in general, microcontrollers come with something called a "development kit."

This kit is usually provided by the manufacturer of the microcontroller.

We use this development kit to work on microcontroller projects.

The development kit is needed to write programs into the microcontroller.

Normally, a special programming tool is required to write programs into a microcontroller.

This development kit also works as that programming tool.

It has many other functions, which I will explain later.

Now, here is a brief explanation of microcontrollers.

Microcontrollers have many functions.

Among these, I will first explain two main functions: "GPIO" and "Timers."

"GPIO" is a kind of digital input/output function.

At this point, I will ask ChatGPT to explain this further.

Explanation of the GPIO Function

Let's also ask about the timer function.

Microcontroller Timer Function

The timer function can be a bit difficult.

We will check it out and, if we have questions about the difficult parts, we will ask as we move forward.

First, we need to connect the microcontroller and the LED.

At this time, we cannot simply connect the microcontroller and the LED with a wire.

Why is that?

Assume that the microcontroller operates at about 3V.

Assume that the LED operates at about 2V.

Think about it.

The microcontroller and the LED operate at different voltages...

If you connect them directly, the difference in voltage can damage the microcontroller or the LED.

So, what should we do?

Connecting the Microcontroller and the LED

Ah, I see!!

Now, let's get it working right away.

The microcontroller development kit already has an LED connected.

How can we make this development kit work?

At this point, a PC is absolutely necessary along with the development kit.

This is because program development is required.

How to Connect the Development Kit

This is difficult!!

It really is difficult!!

However, I will explain it so that everyone can understand.

With a little help from ChatGPT, we will make sure you understand.

Don't worry.

Let's take a break for now.