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Roland Pelayo

I started TMM back in 2015. I’m a firmware and embedded systems engineer with over ten years of experience designing and developing electronic and microcontroller-based products. Over the years, I’ve worked on a wide range of projects, including medical devices, access control and security systems, automation, robotics, wireless communication modules, IoT systems, imaging and sensor instruments, and educational training tools. I’ve built systems using platforms such as PIC, AVR, ESP32, STM32, nRF52, and Raspberry Pi, and I regularly work with protocols like RS485/OSDP, CAN, TCP/IP, Wiegand, and a variety of sensor and communication interfaces. I also develop full-stack solutions for embedded projects, combining firmware, hardware, and web-based dashboards when needed. If there’s a topic you’d like me to write about, or if you need consultation or hands-on development for electronics, embedded, or firmware projects, I’m always open to working on new ideas and collaborations. You can reach me anytime through the contact page.

NodeMCU WiFi Jammer

NodeMCUv1.0 Pinout

There is, in fact, a way to create a NodeMCU ESP8266 WiFi jammer although technically, this is a deauther and not really a jammer. A jammer sends out noise on the WiFi frequency spectrum (2.4 GHz) while the program in this tutorial sends packets that disrupt the normal functions of …

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NodeMCU Pinout Reference

NodeMCU Pinout

The NodeMCU is an Arduino-compatible board that features the ESP8266 at its core. It became popular because it is a WiFi-ready microcontroller by itself - no need for an Arduino. This NodeMCU pinout reference aims to show pinouts for NodeMCU v0.9, NodeMCU v1.0, and NodeMCU v3.

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What is I2C? | Protocol Guide

I2C Wiring Diagram SDA SCL

I2C, or Inter-integrated Circuit, is a communications protocol common in microcontroller-based systems, particularly for interfacing with sensors, memory devices and liquid crystal displays. Similar to SPI, it's a synchronous protocol because it uses a clock line. The I2C protocol, however, uses less pins and is a much more robust standard.

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What is SPI? | Protocol Guide

SPI Timing Diagram

SPI, short for Serial Peripheral Interface, is a communication protocol common in microcontroller systems. Sensors, liquid crystal displays and memory cards are examples of devices that use SPI. It is faster than both UART and I2C although it also has its disadvantages.

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Catch the Light PIC Game

Catch the Light PIC Game

This project is a simple PIC game where LEDs go on randomly one at a time. The objective is to “catch” the LED that’s on by pressing the corresponding button. For every catch, the score, displayed on a seven segment display, is incremented. The speed of the LEDs increase every …

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Using RFID with Raspberry Pi Zero

Using RFID cards and tags is a cool way to switch on anything, wirelessly. For example, you can create an e-lock for your room, check meeting attendance or use cards to control your robot. In this tutorial, we will add RFID functions to a Raspberry Pi Zero.

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Electronic Queuing System

Electronic Queuing System

The idea of this electronic queuing system is to display both sequence number and counter number in three seven segment displays. For example, when counter 1 presses his button, the number 1 shows up on the counter number segment. At the same time, the sequence number is incremented. This system …

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Vibration Sensor Tutorial

SW-420 Vibration Sensor breakout board

Vibrations can be an indicator that trouble is coming. It can be your machine going haywire, a gear on a robot missing teeth, or worse, a looming earthquake! In this vibration sensor tutorial, we will look at how to detect vibrations using specially designed sensors and an Arduino microcontroller.

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