Teach Me Microcontrollers!

The APDS-9960 is probably better known as a gesture sensor. It can detect hand movements such as left, right, up, and down, while also providing proximity sensing. However, the same small module also contains red, green, blue, and clear light-sensing channels. This means we can also use the APDS-9960 as …

Adding an antenna to ESP32 can improve Wi-Fi and Bluetooth reliability when the board is installed far from an access point, placed inside an enclosure, or surrounded by components that interfere with its built-in PCB antenna. However, the modification involves more than soldering a piece of wire to the board. …

The ESP32-S3 analog-to-digital converter works well with low-impedance voltage sources. However, problems can appear when the analog signal comes from a high-value resistor divider, a resistive sensor, or another circuit that cannot supply much current. You may notice that the measured voltage is lower than expected, the first reading is …

A linked list in embedded systems is a collection of data elements connected using pointers. Unlike an array, the elements do not need to occupy consecutive locations in memory. Each element stores its own data and a pointer that identifies the next element in the list. Linked lists are common …

A ring buffer in embedded systems is a fixed-size memory area used to temporarily store data. You will often find one between a fast peripheral and a slower part of the program. A UART interrupt, for example, can place received bytes into a ring buffer while the main application processes …

The ESP32-S3 is commonly powered through its USB port while programming and testing. However, USB power is not always practical for projects installed outdoors, mounted on walls, or placed far from an electrical outlet. In this tutorial, we will build an ESP32-S3 AA battery power supply using two AA cells …

A 16×2 character LCD is enough when you only need to display a few numbers or short messages. However, once your project needs icons, graphs, progress bars, larger fonts, or a proper user interface, a graphical LCD becomes a much better option. In this tutorial, I will show you how …

In this tutorial, we will connect an IR proximity sensor with the ESP32. This sensor is commonly used for obstacle detection, line-following robots, object counters, and simple automation projects where you only need to know if an object is near or not. The common IR proximity sensor module has an …

The RP2040-Zero from Waveshare is one of those boards that looks too small at first glance, but is actually a very capable microcontroller board. It is based on the same RP2040 chip used in the Raspberry Pi Pico, but Waveshare placed it on a much smaller board with a USB-C …

The ESP32-C3 Super Mini is one of those tiny development boards that looks almost too small to be useful at first. But once you plug it in and get past the first upload, it becomes a very handy board for compact Wi-Fi and BLE projects. It is smaller than the usual …