Commons Math is an Apache library which includes a variety of mathematical tools, including 1st and 2nd-order ODE solvers. In order to familiarize myself with the ODE solvers, I wrote a simple program to solve an RC charging circuit. The circuit has these parameters: R (ohms), the resistance of the resistor C (farads), the capacitance…
I’ve recently becoming interested in porting legacy PHP sites to JSPs. It seemed to me that one of the hardest parts of this problem was parsing the PHP code. Once a parse tree was created, the next step would be to emit equivalent JSP code. I went looking for an ANTL4 grammar for PHP,…
I’ve always had a fascination with compilers. As a Java geek, I’m also quite interested in the JVM. In order to learn a little more about both, and as a way to contribute to the open source world, I decided to implement a compiler for BASIC. So, jvmBasic consumes BASIC code and emits .class…
I’ve bee hacking away trying to set up Crochet-BSD to build boot images for Wandboard. Wandboard uses Cortex A9 processor, so it’s ARM. The linux distros for it use U-Boot, so that seemed like a likely place to start for FreeBSD. Looking at the Wandboard Wiki, there is an article on U-Boot which explains how…
Image is here. Boot log is here.
Having built FreeBSD numerous times, I thought it would be interesting to know how to build NetBSD. The instructions from the NetBSD documentation are here. Firstly get the sources. An easy way is to simply FTP them. I got the NetBSD 6.1.2 sources from here. These files are all tarballs, so they’ll need to be…
These are untested builds of FreeBSD-10, created with Crochet Raspberry-Pi BeagleBoard Soekris
I’ve been reading lots of interesting information about iTunes and IOS, so I thought I would investigate, just what is in an iTunes backup. Typically, on OS X, you can find your iTunes backup here, under the appropriate OS X user profile: /Library/Application Support/MobileSync/Backup When you look at the backup, it’s a giant list of…
If you happen to have had an Apple][, you might be interested in retrieving your data from old DOS 3.3 floppies. Or maybe you’re just interested in retrocomputing and downloaded some floppies at Apple2Online. In my case, I had an ulterior motive. I’ve been learning about FreeBSD device drivers and was wondering how difficult it…
Crochet-BSD is a github project which supports building FreeBSD disk images for various platforms such a RaspberryPi, BeagleBoard and others. I had a Soekris 4501 laying around, so I decided to extend Crochet to build images for it. So, firstly, I needed a kernel. Building the kernel config for Soekris is explained pretty well here….