Steve Losh's Blog, page 2

CHIP-8 in Common Lisp: Menus

Our CHIP-8 emulator in Common Lisp is almost complete. It can play games, and we’ve got a rudimentary debugging system in place so we can figure out where things go wrong.
Up to now we’ve been communicating with the running emulator mostly through NREPL or SLIME. This is fine for development, but in this post we’ll add some much-needed polish in the form of menus. This is the kind of boring work that often gets left until the end during game development, so let’s just get it out of the way.

CHIP-8 in Common Lisp: Debugging Infrastructure

Our CHIP-8 emulator in Common Lisp is coming along nicely. It can play games, and in the last post we added a disassembler so we can dump the code of ROMs.
In this post we’ll add some low-level debugging infrastructure so we can set breakpoints and step through code.
The full series of posts so far:
CHIP-8 in Common Lisp: The CPU CHIP-8 in Common Lisp: Graphics CHIP-8 in Common Lisp: Input CHIP-8 in Common Lisp: Sound CHIP-8 in Common Lisp: Disassembly CHIP-8 in Common Lisp: Debugging Infrastructure CHIP-8 in Common Lisp: Menus The full emulator source is on BitBucket and GitHub.

CHIP-8 in Common Lisp: Disassembly

In the previous posts we looked at how to emulate a CHIP-8 CPU with Common Lisp. After adding a screen, input, and sound the core of the emulator is essentially complete.
I’ve been guiding you through the code step by step and it might look simple, but that’s only because I went down all the dead ends myself first. In practice, when you’re writing an emulator for a system you’ll need a way to debug the execution of code.

Projects

The following is a list of projects I’ve created. They’re grouped by maintenance status:
Actively Maintained Under Development Looking for Maintainers Transferred Maintainership Finished Deprecated/Abandoned Actively Maintained These are projects that I’m actively maintaining (for now). I’ll accept patches for them when I have the time.
badwolf is a Vim color scheme. beast is a Basic Entity/Aspect/System Toolkit for Common Lisp. chancery is a library for procedurally generating text in Common Lisp, heavily inspired by Tracery.

CHIP-8 in Common Lisp: Sound

Let's add a buzzer.

CHIP-8 in Common Lisp: Input

Let's add a keypad.

CHIP-8 in Common Lisp: Graphics

Let's draw some pixels.