Article Materials and Resources

January (issue #402) Circuit Cellar

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As individual articles are made available on the website they will be linked on the TOC page-here

4: Building a WebUSB or Web Serial Gadget: You Don’t Even Need an App for That, By Richard Testardi

[1] The Flea-Scope User’s Guide, including a “how it works” section with block diagrams at the end, is here:
[2] The hackaday page for Flea-Scope, with full build instructions (give me a like, and make me smile! :-), is here:
[3] See a video of Flea-Scope in action here:
[4] A number of examples of WebUSB and Web Serial usage, ranging from a simple terminal emulator to the Flea-Scope GUI are here:
[5] The Flea-Scope firmware for the PIC32MK MCU, including both the USB CDC/ACM port as well as all the logic to manage the ADCs, etc., is here:
[6] WebUSB documentation is here:
[7] Web Serial documentation is here:

Microchip Technology |

Code and Supporting Files

10: Backend Wed Development for MCU Clients: Part 3: More Data Exchange, Security, and the Frontend, By Raul Alvarez-Torrico

[1] Raul Alvarez-Torrico, “Backend Web Development for MCU Clients. Part 1. Handling HTTP Requests in PHP.” Circuit Cellar 399, October 2023.
[2] Raul Alvarez-Torrico, “Backend Web Development for MCU Clients. Part 2. Querying a Database in PHP.” Circuit Cellar 400, November, 2023.
[3] ESP8266 NodeMCU HTTPS Requests,
[4] Top 7 PHP Security Issues And Vulnerabilities,
[5] SQL Injection,
[6] Plotly JavaScript Open Source Graphing Library,


ESP8266 NodeMCU CP2102 ESP-12E Development Board
Adafruit BME688 – Temperature, Humidity, Pressure and Gas Sensor – STEMMA QT
How to Upload a File Using the File Manager?
How To Create or Delete a MySQL Database or User
How to add tables to a database in phpMyAdmin

Espressif Systems |

Code and Supporting Files

20: Identifying Musical Chords: Using an RP2040, By Tiffany Chou and Jeff Nan

[1] Protothreads on Raspberry Pi Pico RP2040.
[2] Hunter Adams, Demo Code for VGA Driver.

RP2040 Pinout Diagram.
RP2040 Data Sheet.
Op-Amp Data Sheet.
Microphone Data Sheet (Electret Microphone Amplifier – MAX4466 with Adjustable Gain). /product/1063?gclid=CjwKCAiA9aKQBhBREiwAyGP5ldcS2LZrDPHO5TP5YRw7A3rMfDp1zmeDc96i9LIHtZKfg1KEYXaRaBoCTlkQAvD_BwE
Sallen-Key Topology.
Frequency-to-Note Name Conversions.
RP2040 Demo Code from Hunter Adams:

Code and Supporting Files

26: TECHNOLOGY FEATURE: Home Security Systems: The DIY Options, By Michael Lynes

[1] Lorex for Home:
[2] Google Nest:
[3] Security Informed: How much video surveillance data is stored daily –,to%20over%202%2C500%20petabytes%20daily
[4] Cove:
[5] Aeon Systems:

RadioShack – 150-in-one-Kit Manual: –
Number one Home Security Systems –
Video Surveillance Survey:,a%20THOUSAND%20times%20a%20week.&text=1

Fluent Home |
Kuna AI |
Smart Sentry AI |

32: DATASHEET: Low-Power MCUs: An Industry Race to the Bottom, By Sam Wallace

Infineon PSoC 4000T:
Microchip PIC18F06/16Q20:
Nuvoton MUG51TB9AE:–DS_MUG51_Series_Rev1.00.pdf
NXP Semiconductor Kinetis KL17:
Onsemi RSL15:
Renesas RA2L1:
Silicon Labs EFM32PG28:
STMicroelectronics STM32WL33xx:
Texas Instruments MSPM0L130x:

36: PICKING UP MIXED SIGNALS: Particle IoT Platform Update: Part 1, By Brian Millier

[1] Brian Millier, “Picking Up Mixed Signals: Easing into the IoT Cloud (Part 1): Web Connecting MCUs.” Circuit Cellar 340, November 2018.
[2] Brian Millier, “Picking Up Mixed Signals: Easing into the IoT Cloud (Part 2): Modules in Action.” Circuit Cellar 342, January 2019.
[3] Brian Millier, “GUI-O: A ‘Virtual’ Front Panel: For ESP32 Projects.” Circuit Cellar 389, December 2022.
[4] Particle’s Web IDE Exporter:
[5] Community Tutorial on Pushover Integration:
[6] Tutorial on setting up a ThingSpeak channel and defining a Particle webhook Integration:

DF Robot ESP32C3 Beetle module (DFR0868):
External Bluetooth Antenna: Pulse Electronics W3334B0100,

Particle |

Code and Supporting Files

46: EMBEDDED SYSTEM ESSENTIALS: Binary Breakthrough: Extracting Secrets from Linux Binaries, By Colin O’Flynn

[1] Colin O’Flynn, “Revisiting Code Readout Protection Claims.” Circuit Cellar 384, July 2022.
[2] Colin O’Flynn, “Recreating Code Protection Bypass: An LPC MCU Attack.” Circuit Cellar 338, September 2018.
[3] D-Link Support:
[4] Binwalk repository on GitHub:
[5] Hacking Hardware with a $10 SD Card Reader.$10-SD-Card-Reader.pdf
[6] Ice Ice Baby: Coppin’ RAM With DIY Cryo-Mechanical Robot.

Code and Supporting Files

50: FROM THE BENCH: Air Quality: A Life or Breath Situation, By Jeff Bachiochi

[1] Air Quality Index –
[2] Air Quality Guide for Fine Particulate Pollution.
[3] Sharp GP2Y1014AU0F Datasheet
[4] Sharp GP2Y1040AU0F Datasheet
[5] EPA webpage on home air filtration:

Arduino |
Espressif Systems |
Sharp |

Code and Supporting Files

63: TECH THE FUTURE: The Future of AI and Inclusivity Initiatives: Does AI Foster Inclusivity?, By Ed Watal

Intellibus |

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January (issue #402) Circuit Cellar

by Circuit Cellar Staff time to read: 5 min