Marco's Retrobits

16/03/2026

Advent of Code 2025 with the ZX Spectrum Next – Day 2 Part 2

My solution to the second part of the Day 2 puzzle from the 2025 edition of Advent of Code, implemented in NextBASIC on the ZX Spectrum Next.

16/03/2026

A web tool for converting numbers to and from the floating point format used by the ZX Spectrum. Thanks Martin Vilcans for the original Rust code.

rm-rf: Marco V. (a.k.a. Pulcino)'s site with software (Znake, Frattali.NET), info about music, retrocomputing, retroprogramming, ...

27/02/2026

Better late than never: a new Farmer Sam's Dog Day version (with 64 levels instead of the original 24, bugfixes, new music tracks and more) is finally out!
Go get it: https://retrobits.itch.io/dogday

25/02/2026

https://connect.sdf.org/

"You can log into 28 vintage computer systems in your browser for free, thanks to the Interim Computer Museum — Experience legendary OSes, architectures, programming languages, and games": https://www.tomshardware.com/video-games/retro-gaming/you-can-log-into-28-vintage-computer-systems-in-your-browser-for-free-thanks-to-the-interim-computer-museum-and-sdf-org-experience-legendary-oses-architectures-programming-languages-and-games

11/02/2026

A very useful tool when working with audio files:

Unfortunately, it looks as though either your browser does not support JavaScript or that JavaScript is currently disabled. In order for this calculator to work properly, please enable JavaScript in your browser.

06/02/2026

LaDDDer, my (first?) game has been enlisted to the BASIC 10 Liner Contest 2026. It's a 3D Monster Maze-like videogame in two versions: one for the Sinclair ZX Spectrum and the other one for the Commodore 64. You can download them from the contest page: https://bunsen.itch.io/laddder-zx-sinclair-zx-spectrum-by-marcos-retrobits and https://bunsen.itch.io/laddder-c64-by-marcos-retrobits or play the ZX Spectrum version in your web browser in my itch.io page: https://retrobits.itch.io/lader3d.
Enjoy! 🕹️

BASIC 10 Liner (pseudo-)3D videogame for the ZX Spectrum and Commodore 64

01/02/2026

The 15th edition of the BASIC 10 Liner Contest has started!
https://www.homeputerium.de/

29/01/2026

: solution to Day 2 - Part 1 puzzle in on the , with references to floating point numbers and operations on very big integer numbers.

My solution to the first part of the second puzzle of the 2025 edition of Advent of Code, implemented in NextBASIC on the ZX Spectrum Next.

02/01/2026

Day 1 Part 2 in Next on the

My solution to the 2nd part of the 1st puzzle of the 2025 edition of Advent of Code, implemented in NextBASIC on the ZX Spectrum Next.

28/12/2025

Day 1 - Part 1 in BASIC on the :
my solution to the first puzzle, coded in NextBASIC.

My solution to the first puzzle of the 2025 edition of Advent of Code, implemented in NextBASIC on the ZX Spectrum Next.

18/12/2025

I just released a new version of Lader ( text mode platformer originally coded for the BASIC 10Liner Contest), with 5 new levels and 9 initial lives. The compiled version is currently available for , and Prodest PC128.
Get it from https://retrobits.itch.io/lader (source code available!)
Watch the announcement video for more info and gameplay: https://www.youtube.com/ 🕹️

BASIC 10 Liner platformer for the Commodore 64, Atari 400/800, Sinclair ZX Spectrum, MSX, Amstrad CPC and other 8 bits

21/10/2025

If you like what I do, now you can also support marco's retrobits by offering me a coffee on https://ko-fi.com/marcosretrobits ☕
Thank you! ❤️

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