DEV Community: Rifat

I make a cheaper NTP Clock than Digital Clock with ESP-01

Rifat — Thu, 27 Nov 2025 11:41:11 +0000

Last year, I was working in my lab, and my digital desk clock was running perfectly. Even when I cut off the power, it could still remember the time. But one day, after turning off the lab’s main power, I noticed that the clock suddenly failed to synchronize with the real time.

That incident sparked a big question in my mind—why did this happen? During my research, I discovered that the clock uses an RTC (Real-Time Clock) module, which is powered by a coin-cell battery. That’s when it struck me: the battery might be dead. I replaced the battery, and instantly, the clock started working normally again.

But this raised even more curiosity. I started wondering whether using an RTC is still a convenient method for timekeeping in modern devices. Our phones and computers never lose track of time—so how do they stay synchronized?

Digging deeper, I learned that NTP servers are responsible for maintaining accurate time across connected devices. That revelation pushed me toward a new idea: Why not build my own NTP-synchronized clock?

However, there was a challenge. To access the internet, I needed a microcontroller with Wi-Fi capability. The obvious choice was the ESP series. I first considered the NodeMCU V2, but when comparing prices, I found the RTC module costs around 320 BDT, while the NodeMCU V2 costs 535 BDT—almost double!

So I paused and re-evaluated my options. Then I discovered the ESP-01 module—a compact ESP8266-based microcontroller priced at only 195 BDT.

Wow! Bingo!

This tiny ESP-01 has built-in Wi-Fi and offers nearly the same processing power as a NodeMCU ESP8266 V2, but at a fraction of the cost. That’s when my journey toward building my dream NTP clock truly began.

Why this ESP32-CAM Became My New Favorite Module

Rifat — Sat, 22 Nov 2025 04:37:19 +0000

For the last six months, I have been working with various AI projects, including object detection, gesture recognition, and CNN-based image processing. While experimenting with these models, I gradually became interested in running computer vision directly on microcontrollers. That curiosity led me to explore ESP32-based camera modules. When I first purchased one, I had no idea how to program it. I was familiar with the ESP32 DevKit V1, which includes a micro-USB port for uploading firmware; however, the camera board lacked this convenience. This prompted me to conduct further research, and eventually, I discovered a version of the ESP32-CAM from a native website that comes with an onboard CH340E USB-to-UART interface and a micro-USB port. That discovery made a considerable difference—Bang! That’s where my edge AI journey truly started.

Over the past three months, I’ve grown genuinely attached to this board, mainly because the deeper I explored its architecture, the more engineering elegance I found in it. This tiny module is a remarkable example of optimized embedded design. Usually, from a 7-dollar microcontroller, you expect a basic set of GPIOs, a modest processing frequency, and a few kilobytes of RAM. But the ESP32-CAM offers far more than those standard expectations. It integrates an OV2640 camera sensor directly on the module.

Additionally, it features a microSD card slot for local data storage and a transistor-driven flash LED, mapped to GPIO4, for illumination during image capture. I later discovered the presence of 4MB of PSRAM, which is crucial for buffering image frames and running AI workloads efficiently. The onboard USB programmer and micro-USB interface eliminate the need for any external UART adapters, making development significantly more seamless.

After about a month of working with this board, I was surprised yet again when I realized the module supports an external Wi-Fi antenna using the onboard IPEX connector. The external antenna significantly enhances signal strength, which is crucial for real-time image streaming and low-latency inference over Wi-Fi. And despite integrating numerous components into a compact form factor, the board still exposes 16 header pins, with 10 GPIOs available for custom interfacing and sensor integration. That level of functionality in such a small footprint is genuinely impressive.

It’s impossible not to appreciate the engineering that went into this module. Beyond the peripherals, the core ESP32 itself is loaded with capabilities, including built-in Wi-Fi and Bluetooth, a dual-core 240 MHz Xtensa LX6 processor, 520 KB of on-chip SRAM, and 4 MB of flash memory. All of this comes together to form a powerful edge computing platform that opens the door to real-time AI processing directly on a microcontroller.

5 reason why ESP8266 is best for Developing IoT projects

Rifat — Tue, 11 Nov 2025 10:45:39 +0000

The ESP8266 is becoming increasingly popular among the maker community for IoT Development. Not only that, but in recent years, chip manufacturers have found it very challenging to figure out the secret of their success.

Indeed, the ESP8266 emerged from community engagement rather than the typical path chip manufacturers follow. That is another point of view that brings a different idea to the chip manufacturer.

I have been working with ESP8266 for several years on various types of development, including IoT, Robotics, and embedded systems. I mostly use NodeMCU ESP8266 for my IoT development. I present some of my findings on why the ESP8266 is popular in IoT.

Affordable: Yes, the NodeMCU ESP8266 is a cost-effective option. I usually buy the NodeMCU ESP8266 V2 from TechShopBD, and it costs approximately 500BDT ($4). Even on Amazon, you can buy three of them for $14, which costs roughly $5 per piece. Therefore, the ESP8266 remains significantly cheaper than the sensor.

People would be willing to test it because it is so inexpensive. You won't feel like you're wasting much money even if you break it.

For the ESP8266 to be successful, that is the first step. For the development of IoT, a more individual consumer-focused industry, cost is a considerable factor in development.

Connectivity: ESP8266 chips are equipped with 2.4 GHz Wifi 802.11 b/g/n. For this reason, in the IoT field, where connectivity is more crucial than many other factors, the ESP8266 stands out, as IoT is primarily about sensing data and controlling devices through the cloud. The ESP8266 takes itself several steps further in the Internet of Things.

IoT Development Environment: As more and more people learned about, purchased, and experimented with the ESP8266, they discovered the chip's drawbacks and attempted to make improvements. For instance, to create an IoT project using ESP8266, developers must learn the RTOS SDK and utilize the professional C programming language.

However, an Arduino IDE plug-in or ESP8266 board in the Arduino IDE was later created to enable IoT developers to write ESP8266 command code using the Arduino IDE, thereby reducing development complexity. The creation of Arduino compatibility is a significant accomplishment.

Moreover, several software developers suggested different approaches to IoT development using the ESP8266, including the use of eLua in the NodeMCU project, JavaScript in the Smart.js project, and its conversion to Mongoose IoT Firmware, as well as Python in the MicroPython project.

Abundant Learning Resources: Since Expressif, a Shanghai-based company, makes the ESP8266, the chip information is initially only available in Chinese. However, when it gained popularity, the relevant material was translated into English, which aided in its worldwide promotion.

Textbook publishers became interested in introducing the new chip due to the increasing interest in the ESP8266. The English translation of O'Reilly is currently accessible. There is a dedicated book on the Internet of Things with ESP8266 by Marco Schwartz.

Active Maker Community: Makers working with ESP8266-based development are mainly focused on IoT and home automation projects. When someone starts with ESP8266, they often prefer IoT due to the enormous community support and extensive documentation. It is easy to start IoT development with ESP8266.