Archive for the ‘Operating Systems’ Category

FreeRTOS port for XMOS XS1 processors

Monday, February 22nd, 2010

I have ported FreeRTOS to the XMOS architecture.

The project can be downloaded from the project page on the XCore website. This page will always hold the newest release of the port.

A mirror for the current release can be found here.

Simple Minix 3 driver

Friday, December 25th, 2009

I have made a simple driver for Minix 3 (Tested on Minix 3.1.4, should work on 3.1.5).
This driver controls the caps lock led by writing: write a 0 to /dev/capslockled to turn it off and a 1 to turn it on. Note: this driver is not thread safe as it might interfere with the TTY driver.

The driver can be downloaded here.

Real-time Minix 3

Friday, December 25th, 2009

I’ve been working on a real-time Minix 3 distribution as i have posted about a while ago.

The results of this project can be found on the following website: rtminix3.org.

In short the following was accomplished:

  • Rate-Monotonic scheduling
  • Earliest Deadline First scheduling
  • Run-time switching of real-time scheduler
  • Prioritized message passing
  • Semaphores

Running Minix 3 on a Neoware Neostation 3000

Tuesday, June 16th, 2009

I’ve installed Minix 3 on my Neoware Neostation 3000.

My Neostation 3000 is equiped with a 233MHz AMD Geode processor, 32MB SD-RAM in the SO-DIMM slot, one normal SD-RAM DIMM which was empty during installation ,one IDE interface and RTL8139 network chip (which is supported by Minix). Installing an Operating System on the Neostation is less easy than on a regular PC.  First it does not have a build-in optical drive, but it does have an IDE interface. According to this site the Neostation has problems with two devices on the IDE interface. So you can’t connect both a harddrive and an optical drive at the same time. My ‘harddrive’ is a 4GB Transcend Compact Flash card connected to a CF->IDE converter. I’ve connected my CF card with the converter on an other machine and installed Minix from an optical drive. At the installation i choose to use the RTL8139 card even though my system does not have one. After installation it might hang for a while on not finding the ethernet card but you can skip it by pressing control+c. After the installation was done i’ve removed the CF card and put it in the Neostation and it works fine. I’ve put 256MB extra RAM in the free DIMM slot but onfortunately it only supports 128MB per slot, so only 128MB is usable.  Some other ways to consider installing an OS on the neostation is using an USB drive or copying the image to your drive using an other system.

Neostation 3000 with a Transcend 4GB 133x card on an CF->IDE converter

Neostation 3000 with a Transcend 4GB 133x card on an CF->IDE converter

We don't want a short-circuit do we?

We don't want a short-circuit do we?

Operating systems and MINIX

Wednesday, July 16th, 2008

I am going to do a minor about operating systems for the next half year. What i want to learn is how operating systems work from the inside. What is a better way to learn than using MINIX and the book “Operating Systems Design and Implementation”. The MINIX operating system is written for educational purposes mainly. It’s small, simple and well documented. Because our minor should also have a project we decided to work on the MINIX kernel. After some mail conversations with Andrew Tanenbaum, the author of the book and MINIX we have visited him today at the “Vrije Universiteit Amsterdam” (Free University Amsterdam). Because MINIX3 will also be aimed to run on embedded systems, it is wished to make MINIX3 more real-time. We will work on that.