RetroChipTester firmware update

How to update the firmware of your RetroChipTester with a PICkit 4

Amiga Debugging with Linux

AmigaOS offers a simple debugger via serial port. With a zero modem, you can read the debug output on your PC.

Amiga 1200 Mouse Button Fix

The right mouse button does not work on your Amiga 1200? This is how to fix it.

MaestroPro Internal

The Maestro Professional was a fully digital Amiga sound card. Let's have a look how it worked.

Open-Sourcing old Amiga software

Can modern development methods be applied to old AmigaOS projects? This is how I ported and open-sourced an old Amiga project.

Amiga Assigns

What are AmigaOS "assigns", and why do I miss them on Linux?

Multiplication on a Z80 processor

8-bit processors like the Z80 could only add and subtract numbers. So how were numbers multiplied?

Reading Amiga Harddisks with Linux

How to salvage your data from old Amiga harddisks with Linux

R Tape loading error, Part 2

Find out what's stored on #ZXSpectrum tapes, in this second part.

R Tape loading error

Have you ever wondered how 1980's computers like #ZXSpectrum stored data on tape? Read here how...

Z80 Disassembler

How to write a Z80 disassembler in one afternoon...

Recovering old ZX Spectrum tapes, Part 2

The ZX Spectrum was a comparable cheap home computer, and thus the tape loading and saving mechanisms have not been very sophisticated.

Recovering old ZX Spectrum tapes

Since I am in the mood of heavy ZX Spectrum retro action, I dug out all my old computer tapes in an attept to digitize and convert them. It turned out to be more difficult than I thought...


On a slow processor like the Z80, it is essential to think about execution time. Often a clean approach is too slow, and you need to optimize the code to make it a lot faster.

ZX Spectrum retro game programming

If you are a child of the 1980’s, you maybe remember the Sinclair ZX Spectrum.