The Curious Engineer

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Commodore 8-bitApple / classic MacMath

’05’10’15’20’25
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120 from 1 Jan 2001 to 8 Jun 2026
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monthly (17 in the last year)
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2026 13

  1. Matrix Math on a Commodore 64
  2. The SID Chip Is a Reservoir Computer
  3. WOZMON, Eight CPUs, and a Paper Tape
  4. Forty-Three Quintillion on a Commodore 64
  5. Fixing a Timex Sinclair 2068 and Porting the Bond Maze
  6. Biological Processing Units and a Commodore 64
  7. Breaking Enigma with Index of Coincidence on a Commodore 64
  8. The Wallis Product for Pi on the C64
  9. Enigma Ring Settings on the Commodore 64
  10. Breaking Enigma on the Commodore 64
  11. Enigma Emulator on the Commodore 64
  12. 10 PRINT on the Apple II
  13. The Math Behind Enigma

2025 10

  1. Sorting Algorithms Visualized on the Commodore 64
  2. First Principles: Why You Must Learn Before You Prompt
  3. Dorothy Vaughan: Adapt or Become Obsolete
  4. Three Maze Generators on the Commodore 64
  5. 16-bit Unsigned AND on Commodore 64
  6. The Best Book Cover of All Time
  7. 10 PRINT for the KIM-1
  8. 10PRINT and 100 Doors on the PicoCalc from Clockwork Pi
  9. PICO-8 100 Doors Problem
  10. 10 Print on PICO-8

2024 8

  1. Dragon Curves
  2. 10 PRINT in Rust vs C
  3. wAx the VIC-20
  4. 10 PRINT on the HP-42s
  5. The McNuggets Problem
  6. Back to the basics with BASIC (and Python): Binary Search
  7. Machine Language: Count Faster on 6502
  8. Visualize and verify the reverse engineered Commodore 64 SID LFSR

2023 11

  1. A Gentle Introduction to LFSRs
  2. Quick Post: Printing binary numbers in Commodore BASIC 2.0
  3. 10 Print on the TI-92
  4. A gentle introduction to two's complement
  5. N-Queens problem
  6. Rail Fence Cipher on Commoodore 64 and TI 99/4A
  7. A grid drawing rabbit hole
  8. 10 PRINT on the Rockwell AIM 65
  9. Building a software serial bridge
  10. Blinkenlights
  11. 40 years on, this is still the best maze algorithm

2022 17

  1. Validating Pilish
  2. My mostly retro writing platform contenders in National Novel Writing Month for 2022 NaNoWriMo
  3. Adding very large integers in 8 Bit BASIC
  4. MOS paper tape format
  5. A little more speed from the 6502
  6. How fast can a 6502 transfer memory
  7. Almost primes with TinyBASIC on the KIM-1 clone: PAL-1
  8. VIC’s Revenge, the drop-in replacement for the VIC-20 VIC chip Part 1: Introduction, design goals, and FAQs
  9. 64 Bit Addition and Products on Commodore: The Wheat and Chessboard problem
  10. Vicky-20 S Video Mod Results
  11. Yet another version of the 100 door problem; this time, let's extend Commodore BASIC to add PRINT @, shall we?
  12. Simple exponents on an HP-16c
  13. Fibonacci 1-10 on the KIM-1 (and clones)
  14. The terrible random number generation in the Commodore 64 (and 128)
  15. Getting green and amber screens from a MiniPET 40/80
  16. Simple splitting the screen with two colors on the Commodore 64
  17. A visual 100 Door Problem solution in Python

2021 47

  1. Permutations of 1 to 9 in Python, BASIC, and 6502 Assembly
  2. Making and breaking codes Part 14- VIC Cipher on the Commodore VIC-20
  3. Can you do Advent of Code on 8-Bit Machines?
  4. Quick Tower of Hanoi with Sound on the Commodore 64
  5. Dice frequency
  6. A week of diving a little deeper into my Atari 800XL
  7. Two weeks with a Coco 2 in September
  8. Slot Game On Tandy TRS-80 Pocket Computer PC-4
  9. Calculating Pi via the Gregory-Leibniz series in BASIC on the Tandy Color Computer 2
  10. Just for fun, the 100 door problem on several different systems
  11. Recreational Math Challenge: Border Crossings - but on 40 year old computers
  12. Running Commodore 64 BASIC Programs on a PET
  13. The CERBERUS 2080
  14. Making and Breaking Ciphers with Commodore 64 - The Vigenère Cipher
  15. Making and breaking Ciphers on the Commodore 64, er VIC-20 - Lagged Fibonacci Sequence and a little Monte Carlo while embracing contraints
  16. Quick Post: XOR in Commodore BASIC 2
  17. Running the 8 Bit Show and Tell VIC-20 Super Expander Programming Challenge on the Commodore 64
  18. The retro pinout project
  19. Quick Post: Modulus in BASIC 2 without a cartridge
  20. Making and breaking Ciphers on the Commodore 64 Part 12 - Pontifex - Solitaire from Cryptonomicon
  21. Making and breaking Ciphers on the Commodore 64 Part 11 - One time pads on a Commodore 64, probably a bad idea
  22. Making and breaking Ciphers on the Commodore 64 Part 10 - Finding hash collisions with a type in game from 1984
  23. Making and Breaking Ciphers with Commodore 64 Part 9 - Finding Smallish Primes
  24. Quick Post: Slow text on the Commodore
  25. The Commodore 64 N.O.O.C.U.L.A.R. futbal project
  26. Making and breaking Ciphers on the Commodore 64 Part 8 - RC4
  27. The Nostalgia Files: My all time favorite book
  28. Repairing a Commodore 128 and DIY Chris's RAM tester review
  29. Making and breaking Ciphers on the Commodore 64 Part 7 - Pseudo Random with Linear Congruential Generators
  30. Making and Breaking Ciphers with a Commodore 64 - Part 6: XOR is Magical - Data recovery
  31. Finding the Prodigal Easter Egg inside the Easter Egg on a Commodore 64
  32. Quick post: Determining length in Commodore Assembly
  33. Benchmarking Retro Computers (mostly Commodore) with marginal methods
  34. Jiffies in Assembly
  35. Making and Breaking Ciphers with a Commodore 64 - Part 5: Wargames
  36. Calculating Pi via the Gregory-Leibniz series in BASIC on the VIC-20
  37. Quick Post: Commodore 64 Simple Addition Efficiency
  38. c0pperdragon verdict
  39. Making and Breaking Ciphers with a Commodore 64 - Part 4: The PIN Program from Terminator 2
  40. Making and Breaking Ciphers with a Commodore 64 - Part 3: The Caesar Cipher
  41. Making and Breaking Ciphers with Python, er Commodore- Part 2: The Shift Cipher
  42. Replacing an RF Modulator on a Commodore 64C
  43. Making and Breaking Ciphers with Python, er, a Commodore- Part 1: The Reverse Cipher
  44. Simple, 'unbreakable' encryption with a pencil
  45. Getting started with Native Commodore 64 Assembly
  46. Friday fun: Games I'm playing in Jan 2021
  47. Switching to 64 bit Raspbian Linux is a snap

2020 7

  1. Did you do that on real hardware?
  2. Merry Christmas
  3. My DOScember pick for the best DOS Software
  4. Why does there have to be a why?
  5. Imapenguin, reborn
  6. Vic6560
  7. Resources

2001 7

  1. Imapenguin
  2. 10PRINT on All the Things
  3. CROSSWOZ
  4. CROSSWOZ Manual
  5. Downloads
  6. Faq
  7. Software