Tresoar, the Frisian Historical and Literary Centre has a webcam on its roof that allows one to see the Oldehove in real time via this link. By grabbing and saving an image of the tower every 10 seconds for 24 hours, I was able to create the following video.

I first made a simple shell script to download the latest webcam image every ten seconds. The script looks like this.

#!/bin/bash
let c=1000000;
while [ 1 ];
do
        let c = $c + 1;
        wget http://83.136.192.185/record/current.jpg?rand=$c;
        sleep 10;
done

I got the URL by looking at the image source on the tresoar page. I let this script run for 24 hours starting at midnight. After the script finished I renamed all files using the following command:

rename 's/current\.jpg\?rand=(\d{7})$/current$1.jpg/' \
current.jpg\?rand\=*

The image files are then combined into the final movie by issuing the following command:

mencoder "mf://*.jpg" -mf fps=10 -o oldehove.avi -ovc \
lavc -lavcopts vcodec=msmpeg4v2:vbitrate=800

Of course you should have the required binaries installed.

If people do not believe that mathematics is simple, it is only because they do not realize how complicated life is.

– John von Neumann

The emulator is written in C++ and is available for download here. Besides the program and source code I’ve also included some games that seem to work ok. The original machines that ran a chip-8 interpreter had a 16 key hex-keypad that looked like this:

1 2 3 C
4 5 6 D
7 8 9 E
A 0 B F

This keypad is emulated on the PC keyboard like this:

1 2 3 4
Q W E R
A S D F
Z X C V

Happy gaming!