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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.

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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PIC16F877A - More Microcontroller Features

PIC16F877A

We have managed to blink an LED and use interrupts and timers with the PIC16F84A. Sadly, that’s almost all we can do with that microcontroller as it lacks features that most microcontrollers or Arduino have. From here on, we will now be using the PIC16F877A.

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Bluetooth RC Car

Bluetooth RC Car

This project is basically a remote-controlled car that is controllable via an application installed on a Bluetooth-equipped smartphone. Here's my version of a Bluetooth RC Car.

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Arduino Temperature Sensor

Arduino Temperature Sensor

Project Overview I was recently commissioned to create a simple project for a coffee roasting machine. Basically, I need to measure the temperature of the machine in real time to monitor the progress of the roasting process. This includes a line graph that updates every second and is viewable on …

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Arduino Relay Module Tutorial

Arduino Relay module

A relay is commonly used to interface a low-current circuit to a higher-current circuit. As such, it’s very useful in controlling appliances and other mains-powered devices using microcontrollers. In this Arduino relay tutorial, I will show you how to use a relay with microcontrollers.

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How to Use the MQ-7 Carbon Monoxide Sensor

The MQ-7 carbon monoxide gas sensor is especially designed to be sensitive to carbon monoxide (CO) gas which is emitted by vehicles, factories, etc. Since this gas is considered toxic to humans at certain levels, the concentration of CO is used to determine the air pollution in a given area.

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Adjustable Timer with Relay

Adjustable Timer with Relay

Project Overview This adjustable timer displays seconds, minutes, and hours and is powered by a PIC16F 877A microcontroller. There are five buttons included: start/stop, up for incrementing digits, down for decrementing digits, and left and right for moving between digits during adjustment. I’ve included a relay circuit that will trigger …

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