Back To Basics With An Arduino And An EEPROM

There are plenty of techniques and components that we use in our everyday hardware work, for which their connection and coding is almost a done deal. We are familiar with them and have used them before, so we drop them in without a second thought. But what about the first time we used them, we had to learn somewhere, right? [TheMagicSmoke] has produced just what we’d have needed then for one component that’s ubiquitous, the I2C EEPROM.

These chips provide relatively small quantities of non-volatile memory storage, and though they are not the fastest of memory technologies they have a ready application in holding configuration or other often-read and rarely written data.

Since the ST24C04 512-byte device in question has an I2C bus it’s a straightforward add-on for an Arduino Mega, so we’re shown the wiring for which only a couple of pull-down resistors are required, and some sample code. It’s not the most complex of projects, but it succinctly shows what you need to do so that you too can incorporate an EEPROM in your work.

If learning about I2C EEPROMs piques your interest, perhaps you’d like to read a previous look we made at them.

Hack a Day 25 May 12:00
arduino  eeprom  i2c  i2c eeprom  parts  

Getting to know the new Arduino Nano 33 IoT

The Nano form factor has been a crowd-pleaser amongst makers for years due to its small footprint and ease of integration into any project. As announced at Maker Faire Bay Area, the Nano 33 IoT is part of the new 3.3V variant of the family, adding a pre-certified ESP32-based WiFi and Bluetooth module that brings sophisticated connectivity to its tiny package. The inclusion of an ECC608A crypto chip provides the security that Arduino users are now used to as opposed to other competing solutions that lack a secure key storage.

Today, we sat down with Dario Pennisi, Arduino hardware and firmware development manager, to learn more about the Nano IoT 33.

What are three key features of this board? How will they impact the experience of our users?

1. Secure WiFi and Bluetooth connectivity with a 6-axis IMU.

2. Pre-certified module with external processor ensures maintaining RF compliance when writing application code versus ESP32 modules where modifying code impacts certification.

3. On-board DC-DC power supply enables the board to be powered up to 21V maintaining high efficiency and offering a lot of current to external devices without overheating. This is a big improvement over other products on the market that have LDO and heat up quite a bit when powered at high voltages.


What are a few applications and why is this board a great option for them?  

1. Add WiFi and Bluetooth connectivity with strong security to all the existing Arduino Nano applications.

2. On-board IMU can be used to wirelessly monitor vibration, orientation, and rotational speed of small objects thanks to its lightweight and compact form factor.

3. Run directly from high voltages from lead or multi-cell Lithium-ion batteries providing 3.3V power supply to peripherals at significant output current.

Which Arduino board is the most similar to the Nano 33?

The Nano 33 IoT is essentially a MKR WiFi 1010, but sacrifices a battery charger and shield compatibility in favor of a miniaturized footprint and lower cost. The Nano 33 IoT is built around the ESP32, which is primarily aimed at WiFi but supports Bluetooth as well, although with higher power consumption than the Nano 33 BLE.

Sending Sensor Data to Android Phone using Arduino and NRF24L01 over Bluetooth (BLE)

Bluetooth Low Energy (BLE) is a version of Bluetooth and it is present as a smaller, highly optimized version of the classic Bluetooth. It is also known as Smart Bluetooth. The BLE was designed keeping in mind the lowest possible power consumption specifically for low cost, low bandwidth, low power and low complexity. ESP32 has inbuilt BLE capabilities but for other microcontrollers like Arduino, nRF24L01 can be used.

Circuit Digest 24 May 12:57

Little Flash bumps around on supercapacitor power

Supercapacitors are intriguing power sources, and while they don’t hold as much total energy as a battery, they can store and release charges in an instant. To take advantage of this interesting properly, Mike Rigsby created the ‘Little Flash‘ rover.

This device uses a pair of continuous rotation-modded servos to move about for roughly 20 minutes. It’s controlled by an Arduino Uno, and employs over-current detection as well as a bump switch to keep it from getting stuck. 

The coolest feature, however, is that it’s powered by a bank of three 350 farad supercaps in series. The capacitor setup allows it to charge in seconds, though with a current flow of nearly 50 amps, charging experimentation wisely took place with Rigsby some distance away!

ThingSpeak não mostra dado (IoT Based Patient Monitoring System using ESP8266 and Arduino)

Circuit Digest 23 May 19:45

IoT Based Biometric Attendance system using Arduino and Thingsboard

Few years back if you were to tell someone that the Geyser and bedroom lights in your home are connected to internet, they would be baffled and might even criticize it as over-engineered products. But today with the advent of IoT, Smart cities etc the idea no longer sounds strange, we have devices around us that have become smarter by being able to communicate with the internet.

Circuit Digest 23 May 09:26

Electric typewriter turned CNC plotter

A few months ago, maker Fabian Mazza created a CD ROM plotter for his daughters. While the three-year-old loves it, the eight-year-old thought it was too small. Rather than giving up—or building a CNC machine from scratch—he cleverly constructed a new plotter out of a Smith Corona electric typewriter.

Since this device is designed to control the X and Y positions of a writing implement using steppers, it gave him everything he needed for CNC use via an Arduino Uno and GRBL shield.

For better resolution, he added gear reduction to the carriage stepper salvaged from an old scanner. Z-axis movement is done using parts from a DVD-ROM to control whether the pen lowered onto the paper or retracted.


Tom Stanton’s trebuchet altitude measurement “golf ball”

YouTuber Tom Stanton built a trebuchet about a year ago. Now, in order to figure out just how high it can toss something, he designed a custom altitude tracking device in the form of an oversize golf ball. 

An Arduino Nano is squeezed inside this sphere, along with a battery, an altimeter, an accelerometer, and even a small servo. The altimeter is used for primary height measurement, while the accelerometer detects launches. A servo then deploys a parachute four seconds later to keep the electronics safe.

As it turns out, the trebuchet is able to fling the ball in the air 60 meters. While impressive, per Stanton’s discussion, it may not be as efficient as you might suspect! Be sure to check out the project in the video below! 

The first-ever Arduino certification is now available

The Arduino Certification Program (ACP) is an Arduino initiative to officially certify users at different levels and confirm their expertise in key areas. Certifications are offered at three tiers — enthusiasts, educators and professionals — which have been identified as the largest Arduino user groups through extensive feedback from the community.

And today, we are excited to announce the availability of the initial Arduino certification: Arduino Fundamentals, which is the first release of the ACP. Access to the exam leading to the certification can be purchased either in combination with the Arduino Starter Kit or as a standalone exam.

The Arduino Certification: Fundamentals Exam is a structured way to enhance and validate your Arduino skills, and receive official recognition as you progress. Anyone interested in engaging with Arduino through a process that involves study, practice, and project building is encouraged to pursue this official certificate.

Developed in consultation with leading technology curriculum, interaction design, and electronic engineering professionals, the Arduino Certification: Fundamentals Exam assesses skills based on exercises comprised of practical tasks from the Arduino Starter Kit.

The official assessment covers three main subjects: theory and introduction to Arduino, electronics, and coding. During the exam, you will be asked to answer 36 questions of varied format and difficulty in 75 minutes.

Questions will test your knowledge on the following topics:

  • Electricity
  • Reading circuits and schematics
  • Arduino IDE
  • Arduino boards
  • Frequency and duty cycle
  • Electronic components
  • Programming syntax and semantics
  • Programming logic

The certification is currently only available in the US, but will be opened in more countries during 2019. If you’d like to learn more about Arduino Fundamentals, download the user guide. Additional information can also be found here.

Single-sensor selfies with the Flying Pixel Portrait Camera

While most cameras use an array of sensors to quickly capture an image, Niklas Roy presents a different take on things with his Flying Pixel Portrait Camera.

This installation invites participants to place their head under a shroud for nearly a minute and a half, while a computer-controlled projector scans one’s face pixel by pixel. Reflected light levels are recorded with a single light-dependent resistor (LDR) via an Arduino flashed with Firmata, allowing it to interface with the Processing sketch that runs the device without any extra software.

The results are 50×50 black and white photos. It’s also possible to produce color images, which means triple the wait time—and a bit more noise.

The Flying Pixel Portrait Camera uses a video beamer, a single photo resistor, an Arduino and a PC for taking photos of people’s faces. The beamer ‘scans’ the image by projecting a small white square onto a person’s face inside an otherwise completely dark chamber. While the projected square slowly moves over the entire face, the photo resistor captures the reflected luminosities. This generates a proportional analog electric signal which is digitized by an Arduino and transmitted to the PC. As the PC also controls the position of the projected square, it can now construct an image based on the different brightness values that it receives, one pixel at a time.