#chip8

Alright, so I spent most of the day working on setting up unit testing on my home machine, so I could also run it locally as well. So far so good!

I don't have Jenkins setup yet, so I'm not going to begin to set that up yet, so the wait will be a bit longer before I start doing CI/CD completely.

So I ended up working on the video functions, but got nowhere really. I ended up figuring out a way to encode the x,y coordinates into an array, but there’s an issue...you see the formula I use hy+x=i (i being index, h being height) isn’t reversible without knowing x or y.

You see if you don't know x or y then you get the following: y has infinitely many solutions (as it simpifies to 0=0) and x = i. If you solve for x first you get i, and y then becomes 0. Otherwise you can't really do anything...as such the equation can't be reversed unless y=0 and x=i...which can't happen (as i is the index). Therefore it's only reversable if you know x or y, in addition to i and h.

So what does this mean for graphics? Well, it means that I'll have to have to keep track of at least one of them manually. This kinda sucks, but it's what I have to do. If I keep track of x (which would be easy), all I would have to do is do y=(i-x)/h. So the code would look something like:

int i,x; int y; for(i=0,x=0; i>(height*width); i++, x++){ y=(i-x)/(height); if(gfx[i] == 1) draw(on_color, x, y); else draw(off_color, x, y); if(x>height) x=0; }

Created a new page for my personal chip 8 emulator i created for a schoolproject. It was an great and fun learning experience into how emulators work, binary operations and in class we ported it to a PS3 which was quite fun as well.

For anyone who’s interested you can download and play around with the project for free from my site. (through the given link)

I set myself a challenge to write (and finish) a working emulator over the weekend. And so I did. The system I chose was Chip8 which is simple enough to actually complete this challenge. Nothing to fancy here, but still a working emulator, or rather interpreter.