Article Materials and Resources

September (issue #362) Circuit Cellar

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p.6: Machine Vision Random Number Generator: Using the Raspberry Pi, By Devlin Gualtieri

[1] Random page feature on Wikipedia (
[2] M. Matsumoto and T. Nishimura, “Mersenne Twister: A 623-Dimensionally Equidistributed Uniform Pseudo-Random Number Generator”, ACM Transactions on Modeling and Computer Simulation, vol. 8, no. 1 (January, 1998), pp 3-30, doi:10.1145/272991.272995.
[3] Takuji Nishimura, “A C-program for MT19937: Integer version,” April 6, 1998.
[4] Landon Curt Noll, Robert G. Mende and Sanjeev Sisodiya, “Method for seeding a pseudo-random number generator with a cryptographic hash of a digitization of a chaotic system,” US Patent No. 5,732,138, March 24, 1998 ( )
[5] Joshua Liebow-Feeser, “Randomness 101: LavaRand in Production,” Cloudflare Web Site ( ).
[6] Dina Kozlov, “League of Entropy: Not All Heroes Wear Capes,” Cloudflare Web Site ( ).
[7] Raspian Download Page ( ).
[8] Dieharder: A Random Number Test Suite at Robert G. Brown’s General Tools Page ( ).

Appendix I – List of Source Code Files for the Raspberry Pi Machine Vision Random Number Generator

1.  prng.c (c source code for main program)

2. (python source code for I2C interface)

3.  prng_log.php (web browser interface program)

ON Semiconductor|
Raspberry Pi Ltd. |
Texas Instruments (TI) |

p.16: Write an Object Tracking Drone Application: Using OpenCV, MAVSDK and PX4, By Raul Alvarez-Torrico

[1] “Writing MAVSDK/PX4 Drone Applications” in Circuit Cellar 361 (August 2020)
[2] Figure 4 image source:
[3] Thresholding Operations using inRange,
[4] Moments: Find the Center of a Blob (Centroid) using OpenCV (C++/Python)
[5] Drawing Functions in OpenCV

Demo Videos of ‘’

Smoothing Images

Thresholding Operations using inRange

The Ultimate Guide to Understanding Hue, Tint, Tone and Shade

Ardupilot |
PX4 Autopilot |
QGroundControl |

p.26: Forearm-Controlled Robotic Hand: Sensors and Servos, By Cassandra Scarpa and Caeli MacLennan

[1] Tendon use in amputees.
Smith, D.G., General Principles of Amputation Surgery. Chapter 2 in Atlas of Amputation and Limb Deficiencies.
[2] 3D hand model
[3] Flex sensor datasheet
[4] Multiplexer datasheet
[5] Demo video

Digi-Key |
Microchip Technology |
Texas Instruments |

p.34: Frequency Independent Phase Shifter: Precise Solution, By Nishant Mittal


FET as Voltage controlled Resistor AN105, Siliconix 1997

Variable frequency passive phase shifter, Flarity Warren H

Texas Instruments |

p.38: Build a Music Composition Assistant: PIC32-Based PICcompose, By Tara van Nieuwstadt and Laasya Renganathan


Video of PICcompose project:

Adafruit |
Microchip Technology |

p.42: Embedded Solutions Step Up for Robotics Duties: Systems, Boards and Chips, By Jeff Child

ADLINK Technology |
Advanced Motion Controls |
Congatec |
Maxon |
Qualcomm |
Renesas Electronics |
Sparkfun |
STMicroelectronics |

p.49: Rugged SBCs Bulk Up for Harsh Environment Work: Toughness Trending, By Jeff Child

[1] “TS-IRIDIUM Global Communications Solution”, by Derek Hildreth, from Technologic Systems blog

Advantech |
American Portwell Technology |
Avalue Technology |
Axiomtek |
Gateworks |
Kontron |
Technologic Systems |
WinSystems |

p.55: DATASHEET: Application-Specific MCUs: Focused Feature Sets, By Jeff Child

Infineon Technologies
Maxim Integrated
Microchip Technology
NXP Semiconductors
Renesas Electronics
ST Microelectronics


Infineon Technologies
Maxim Integrated
Microchip Technology
NXP Semiconductors
Renesas Electronics
ST Microelectronics

p.58: EMBEDDED SYSTEM ESSENTIALS: IC Packaging and Physical Security: Do They Affect One Another?, By Colin O’Flynn

[1] “Yet Another Fault Injection Technique : by Forward Body Biasing Injection” by P. Mourine et al. ( ).

NewAE Technology |
STMicrolectronics |

p.62: PICKING UP MIXED SIGNALS: Customer Counter Uses ESP32 MCU: A COVID-19 Era Tool, By Brian Millier

ESP32 DevKit-C    Manufacturer’s web-page

ESP32 Arduino Core library/boards package :

MFRC522 RFID reader
Search for “RC522.” There are many different sources for this module and the key-tags.

HC-SR04 Ultrasonic Range Module
Search for “HC-SR04.” There are many sources for this module.

LED Matrix display 32X8 Red
Search for “CANADUINO 32X8 Matrix LED” or×8-64-dot-matrix-4-modules-arduino-raspberry-stm/

Unit Enclosure:  Hammond 1455T2202

Ultrasonic Sensor Enclosure:  Hammond 1591AFBK

Warning light Column:
This is the product I used. As mentioned in the text, I had to modify it to work on 12V, so this is not an ideal choice.

Adafruit |
Digi-Key Canada |
Espressif Systems |
Maxim Integrated |
Microchip Technology |
Murata Power Solutions |
STMicrolectronics |
Traco Power |

p.70: FROM THE BENCH: Dusting Off the Vinyl: Wireless-Connected Turntable, By Jeff Bachiochi


Maxim Integrated |
Serpac Electronic Enclosures |
ZhuHai JieLi Technology |

p.79: The Future of Workplace Productivity: Low-Power IoT Networking Solves Smart Building Challenges, By Byron BeMiller

[1] JLL’s 3-30-300 rule
[2] Berg Insight
[3] IoT Analytics

LoRa Alliance |

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