clownmdemu – Adding Mega CD Support

I’ve been thinking of expanding my Mega Drive emulator with support for the Mega Drive’s add-on – the Mega CD. On paper, this should be simple enough to do: while the Mega CD adds a second 68000 CPU, communications ports, a lot of extra RAM, hardware for graphics-transformation, a sound chip, the titular CD drive,

clownmdemu – frontend v0.4.1-v0.4.3, libretro v0.2.1-v0.2.3

Native File Dialogs for Linux and the BSDs As promised in the previous emulator blog post, I’ve added native file dialogs for Linux and the BSDs. These leverage the Zenity and kdialog tools, providing native GTK- and Qt-based file dialogs respectively. Presumably, these will work on other operating systems too, as long as they provide

clownmdemu – frontend v0.4 & libretro v0.2

Custom Dear ImGui Style Dear ImGui’s default style looked a bit tacky and ‘programmer art’-like to me, so I’ve made my own: I’ve tried to create a typical ‘dark mode’ theme while still keeping a high degree of contrast in order to maintain good legibility. Another focus of the style is technical and artistic minimalism,

clownmdemu – frontend v0.3.1

This is just a quick update to address some issues in the previous v0.3 release. Make FM Debugger More Compact The FM debugger was a bit ‘verbose’ in v0.3… As you can see, each channel was given its own window, which meant that it was a lot of effort to simply switch from one channel

clownmdemu – frontend v0.3 & libretro v0.1.1

This update mostly affects the standalone frontend, but a couple of them also apply to the libretro core. Keyboard Rebinding One shortcoming of the standalone frontend is that it lacks keyboard rebinding: the W, A, S, and D keys will always control the Control Pad’s D-Pad, and so on. But not anymore! New to the

clownmdemu – frontend v0.2 & libretro v0.1

It’s been too long, but finally my emulator has an update! Since the first release, the emulator has been greatly optimised, some inaccuracies in the 68000 interpreter have been addressed, and the occasional missing CPU instruction has been added. Compatibility with games should be a bit better than before, but still not great as many essential

Git Split

My Mega Drive emulator has gotten pretty big: it has multiple core components (68000 emulator, Z80 emulator, YM2612 emulator, etc.) two separate frontends (a standalone SDL2/Dear Imgui frontend, and a libretro frontend), and even some tools which I never committed like a 68000 test suite and a performance benchmarker. This all creates a pretty bloated

Virtual 68 Katy

At last, it’s working! After writing the last blog post, I was able to find a test suite for the Motorola 68000, allowing me to verify the accuracy of my 68000 emulator. After addressing a number of inaccuracies, Linux could finally finish booting! The issue that was breaking kmalloc was the CMPA.W, ADDA.W, and SUBA.W

(Almost) Emulating the 68 Katy

During a recent bout of illness I became fascinated with the concept of porting the Linux kernel to minimalist environments: it began when I stumbled upon this video of someone who had gotten Linux running on their RISC-V emulator, which made me wonder if I could do the same with my 68000 emulator. Unfortunately, I

clownmdemu – 68k Overhaul

Ever since adding support for the Z80, the next improvement that I wanted to make to my emulator was overhauling the 68k CPU interpreter. As detailed in the first emulator-related blog post, the 68k CPU interpreter was one of the first parts of the emulator that I created. It was also the first CPU interpreter