@gloriouscow.bsky.social
Developer of MartyPC - a cycle-accurate IBM PC/XT Emulator
https://github.com/dbalsom/martypc
and fluxfox - a PC floppy disk image library
https://github.com/dbalsom/fluxfox
Retro enthusiast and shameless computer geek
https://github.com/dbalsom/martypc
and fluxfox - a PC floppy disk image library
https://github.com/dbalsom/fluxfox
Retro enthusiast and shameless computer geek
More MOO-related pixel art
November 15, 2025 at 7:05 PM
More MOO-related pixel art
more flux cats?
November 10, 2025 at 10:17 PM
more flux cats?
November 10, 2025 at 10:08 PM
I did work on a few angles of Scar sprites to replace the spider mastermind, he was going to have been behind it all
November 10, 2025 at 9:53 PM
I did work on a few angles of Scar sprites to replace the spider mastermind, he was going to have been behind it all
November 10, 2025 at 6:41 PM
From Infoworld, July 1983.
My guy generated SIX FEET of code. How many feet of code did you write today?
#retrocomputing
My guy generated SIX FEET of code. How many feet of code did you write today?
#retrocomputing
November 5, 2025 at 3:19 AM
From Infoworld, July 1983.
My guy generated SIX FEET of code. How many feet of code did you write today?
#retrocomputing
My guy generated SIX FEET of code. How many feet of code did you write today?
#retrocomputing
The test suite includes 941 test files (406 opcodes plus operand size and address size prefix combinations) comprising 1,758,700 individual, heuristically-generated instruction tests, all of them containing cycle exact captures of the execution of a real 386 CPU under the control of an Arduino Giga.
November 4, 2025 at 8:16 PM
The test suite includes 941 test files (406 opcodes plus operand size and address size prefix combinations) comprising 1,758,700 individual, heuristically-generated instruction tests, all of them containing cycle exact captures of the execution of a real 386 CPU under the control of an Arduino Giga.
I've officially released my real-mode emulator CPU test suite for the Intel 80386.
github.com/singlestepte...
#retrocomputing #emulation
github.com/singlestepte...
#retrocomputing #emulation
November 4, 2025 at 8:16 PM
I've officially released my real-mode emulator CPU test suite for the Intel 80386.
github.com/singlestepte...
#retrocomputing #emulation
github.com/singlestepte...
#retrocomputing #emulation
Here's a super closeup zoom of two PROLOK holes on a 5.25" diskette:
This is from a later version of PROLOK, v5 - apparently they decided the solution to the problem of PROLOK getting cracked was MOAR HOLES.
This is from a later version of PROLOK, v5 - apparently they decided the solution to the problem of PROLOK getting cracked was MOAR HOLES.
November 1, 2025 at 9:06 PM
Here's a super closeup zoom of two PROLOK holes on a 5.25" diskette:
This is from a later version of PROLOK, v5 - apparently they decided the solution to the problem of PROLOK getting cracked was MOAR HOLES.
This is from a later version of PROLOK, v5 - apparently they decided the solution to the problem of PROLOK getting cracked was MOAR HOLES.
Here's what FREAKING LASER BEAMS do to the data on a floppy disk.
November 1, 2025 at 9:03 PM
Here's what FREAKING LASER BEAMS do to the data on a floppy disk.
Here's a fun example of a "marching bits" protection, even more devious than fuzzy bits.
November 1, 2025 at 8:56 PM
Here's a fun example of a "marching bits" protection, even more devious than fuzzy bits.
A rare example of Vault Corporation's "PROLOK" copy protection scheme on a 3.5" floppy disk.
Vault used some method - probably a laser - to remove the oxide coating from one side of the mylar disk, making it impossible to write to.
#retrocomputing
Vault used some method - probably a laser - to remove the oxide coating from one side of the mylar disk, making it impossible to write to.
#retrocomputing
November 1, 2025 at 8:29 PM
A rare example of Vault Corporation's "PROLOK" copy protection scheme on a 3.5" floppy disk.
Vault used some method - probably a laser - to remove the oxide coating from one side of the mylar disk, making it impossible to write to.
#retrocomputing
Vault used some method - probably a laser - to remove the oxide coating from one side of the mylar disk, making it impossible to write to.
#retrocomputing
Before I got deep into the retro computing hobby, I dabbled in watercolors.
My art desk is now an electronics workstation cluttered with equipment and various Arduino projects.
I kinda miss painting though. I wish I had the space to have both hobbies.
#watercolor
My art desk is now an electronics workstation cluttered with equipment and various Arduino projects.
I kinda miss painting though. I wish I had the space to have both hobbies.
#watercolor
October 27, 2025 at 4:34 PM
Before I got deep into the retro computing hobby, I dabbled in watercolors.
My art desk is now an electronics workstation cluttered with equipment and various Arduino projects.
I kinda miss painting though. I wish I had the space to have both hobbies.
#watercolor
My art desk is now an electronics workstation cluttered with equipment and various Arduino projects.
I kinda miss painting though. I wish I had the space to have both hobbies.
#watercolor
made a lil mascot for my MOO-format for emulator CPU tests
i've always done pixel art in photoshop but maybe i should try aseprite someday
i've always done pixel art in photoshop but maybe i should try aseprite someday
October 25, 2025 at 4:38 PM
made a lil mascot for my MOO-format for emulator CPU tests
i've always done pixel art in photoshop but maybe i should try aseprite someday
i've always done pixel art in photoshop but maybe i should try aseprite someday
if Simba had simply had a Remington 870 then the movie would have gone quite differently
October 23, 2025 at 3:36 AM
if Simba had simply had a Remington 870 then the movie would have gone quite differently
not to toot my own horn but these pain face sprites went hard
October 23, 2025 at 3:24 AM
not to toot my own horn but these pain face sprites went hard
@davidxnewton.bsky.social
i recently found some assets from a DOOM TC I started (and never had a hope of finishing) sometime in 1995
LION KING DOOM
i recently found some assets from a DOOM TC I started (and never had a hope of finishing) sometime in 1995
LION KING DOOM
October 23, 2025 at 3:22 AM
@davidxnewton.bsky.social
i recently found some assets from a DOOM TC I started (and never had a hope of finishing) sometime in 1995
LION KING DOOM
i recently found some assets from a DOOM TC I started (and never had a hope of finishing) sometime in 1995
LION KING DOOM
thank you cyberpower for logging UPS stats every 3 seconds since the dawn of time
October 23, 2025 at 12:54 AM
thank you cyberpower for logging UPS stats every 3 seconds since the dawn of time
There's a legend in the lower left that explains what you're looking at. I hope the pattern is a bit visually obvious.
You're looking for anything that deviates from the legend. We're trying to categorize three different sizes of transistor.
You're looking for anything that deviates from the legend. We're trying to categorize three different sizes of transistor.
October 18, 2025 at 9:24 PM
There's a legend in the lower left that explains what you're looking at. I hope the pattern is a bit visually obvious.
You're looking for anything that deviates from the legend. We're trying to categorize three different sizes of transistor.
You're looking for anything that deviates from the legend. We're trying to categorize three different sizes of transistor.
I was impressed by the CRT too. Thomas is brilliant.
October 16, 2025 at 5:06 PM
I was impressed by the CRT too. Thomas is brilliant.
I've decoded the NEC V20's group decode PLA.
This PLA takes an 8-bit opcode (and two mode signals) as inputs and produces 14 status outputs that control operation of the CPU.
These status signals will hopefully explain some gaps in functionality that the microcode doesn't cover.
#retrocomputing
This PLA takes an 8-bit opcode (and two mode signals) as inputs and produces 14 status outputs that control operation of the CPU.
These status signals will hopefully explain some gaps in functionality that the microcode doesn't cover.
#retrocomputing
October 13, 2025 at 3:43 PM
I've decoded the NEC V20's group decode PLA.
This PLA takes an 8-bit opcode (and two mode signals) as inputs and produces 14 status outputs that control operation of the CPU.
These status signals will hopefully explain some gaps in functionality that the microcode doesn't cover.
#retrocomputing
This PLA takes an 8-bit opcode (and two mode signals) as inputs and produces 14 status outputs that control operation of the CPU.
These status signals will hopefully explain some gaps in functionality that the microcode doesn't cover.
#retrocomputing
Here's a visualization of the NEC V20 microcode showing how the microcode is organized into logical sections. Over half of it implements the 8088 ISA, with many of the internal functions implementing common routines for division, multiplication and string operations.
#retrocomputing
#retrocomputing
October 11, 2025 at 1:06 AM
Here's a visualization of the NEC V20 microcode showing how the microcode is organized into logical sections. Over half of it implements the 8088 ISA, with many of the internal functions implementing common routines for division, multiplication and string operations.
#retrocomputing
#retrocomputing
The individual bits are encoded via these structures - an opening encodes a 1, the lack of an opening represents a 0.
There are 29K bits in the microcode array.
There are 29K bits in the microcode array.
October 6, 2025 at 12:19 AM
The individual bits are encoded via these structures - an opening encodes a 1, the lack of an opening represents a 0.
There are 29K bits in the microcode array.
There are 29K bits in the microcode array.
Here's the microcode ROM from the NEC V20.
Cycle accurate V20 emulation? If we can decode it...
#retrocomputing #emulation
Cycle accurate V20 emulation? If we can decode it...
#retrocomputing #emulation
October 6, 2025 at 12:19 AM
Here's the microcode ROM from the NEC V20.
Cycle accurate V20 emulation? If we can decode it...
#retrocomputing #emulation
Cycle accurate V20 emulation? If we can decode it...
#retrocomputing #emulation
I'd like to shoutout @pcbwayofficial.bsky.social for sponsoring this run of my #ArduinoX86 V4 boards.
The FPU board is my first 4-layer board so I'm hoping I didn't make any fatal mistakes.
#retrocomputing #emulation
The FPU board is my first 4-layer board so I'm hoping I didn't make any fatal mistakes.
#retrocomputing #emulation
October 5, 2025 at 1:53 PM
I'd like to shoutout @pcbwayofficial.bsky.social for sponsoring this run of my #ArduinoX86 V4 boards.
The FPU board is my first 4-layer board so I'm hoping I didn't make any fatal mistakes.
#retrocomputing #emulation
The FPU board is my first 4-layer board so I'm hoping I didn't make any fatal mistakes.
#retrocomputing #emulation