After having published my tutorial about sending SMS with the ESP32, I received some comments via the contact form of my website asking a way to send notifications for free. Today I’ll show you a way to do it; it will be also the occasion to write about IFTTT service and about developing custom components for the…
When you surf on the Internet, the DNS (Domain Name System) service has the job of “translating” (resolve) the hostnames to the corresponding IP addresses. If, for example, you type www.google.com in your favorite browser, your computer queries the DNS server – usually the one managed by your provider – and gets from it the IP…
Pi Zero is a small board – part of the Raspberry family – designed for embedded applications where space is a constraint. The low cost (about 10€ for version W, with wifi connectivity) and the ability to run different operating systems makes it the ideal choice for different applications (media centers, data loggers…). Raspberry Pi Zero unfortunately doesn’t offer a dedicated audio…
On 6th of April, Espressif published version 2.0 of the esp-idf framework. The complete list of the new features and the bugs fixed is available on Github, let’s see the most important ones (in my opinion ;)): [checklist] they included or made stable new drivers for peripherals like I2C, I2S, SPI Master, SDMMC you can now run a serial…
After having brought a Raspberry Pi Zero, I asked myself how to access it and do some initial configuration because of in that moment I hadn’t an HDMI monitor or an USB keyboard and a mouse. Fortunately, this Raspberry model supports USB OTG (On The Go): it can “become” a slave USB device such as a…
When designing and developing an embedded application, you often need to implement a way to notify the user if a specific event or condition is reached. Let’s imagine for example an house alarm system that must inform the owner if the front door is open when he’s away… In today’s tutorial I’ll show you how…
In a previous blog post, I started explaining how to use the esp32 pins for Input/Output operations. Today I’ll show you how to take advantage of the interrupts the pins can generate. Interrupts In computer technology, an interrupt is a signal that indicates the occurrence of a specific event which requires immediate attention. The interrupt signal therefore blocks the normal…
After having published my previous article, I received some comments asking what was the purpose of a random number generator, like the one included in the esp32 chip. Random numbers are widely used in cryptography and a good random number generator is very important to assure an high level of security, as well-explained in Cloudflare’s…
Today a short tutorial that will explain how to use the random number generator, a peripheral included in the esp32 chip. It’s also an opportunity to show how to interact with internal peripherals and to understand some additional details about how the framework is designed. Address space Both the esp32 CPUs (PRO e APP) share (with some minor…
With this tutorial we’re going to start using the I/O pins of the esp32 chip. The chip features 40 General Purpose I/O pads (GPIO), that are 40 “contacts” you can use in different ways, both for input and output functions. The setup of those pads is quite complex: the esp32 chip allows indeed to “map” the internal…