Someone built a functioning 16-bit CPU inside Microsoft Excel with its own custom language

Building a functioning 16-bit processor or CPU inside Microsoft Excel, with its own memory, output, and custom assembly language, is an impressive - if not entirely useful - feat. This is because you're looking at a 16-bit CPU with a clock speed of just 3 Hz, 128KB of RAM, and a 16-color output display.

But this isn't Intel's iconic 8086 CPU recreated in Excel, as it features its own custom architecture and instruction set. YouTube channel Inkbox breaks down how they created a functioning CPU inside Excel in a fascinating and informative 15+ minute video above.

The Microsoft Excel CPU was made possible due to how a spreadsheet app works - where, with each cell, you've got a powerful calculator that can take in data and output a result. Stack them together, and they can mimic a CPU's input and output functionality, albeit from the era when MS-DOS was the height of cutting-edge technology.

What's even more impressive than the fact that it works is that you're also looking at pure Excel in that the custom CPU was built without any Visual Basic scripts or plugins. So, you've got a CPU in an Excel file that anyone running Microsoft Office can fire up. The video provides an excellent crash course in how CPUs function, and by creating a custom assembly language called Excel-ASM15, we get to see how it performs operations and executions.

It's not every day you get to see such a cool and impressive little project come to fruition, and it reminds us (and others) of CHUNGUS 2 - a massive virtual and working CPU created in Minecraft in 2021.