Tuesday, August 14, 2012

Linux-0 #2: Getting files inside Minix

According to the linux-0.01 release notes, gcc-1.40 was used and 1.37.1 is mentioned but with a slight note. Googling for 1.4.0 against minix 1.x didn't turn up anything but 1.37.1 did. Thought I'll try to get 1.37.1 running then compile 1.4.0 on that.

But first I needed to figure a way to get files inside the minix system.

The best method I found was to create a dos partition then use the dos* utilities to read files. I hooked the qemu hd image via loop device (losetup and kpartx), good thing I used the raw format. Creating and formatting the partition on linux was problematic, minix can't read files from it.

The problem stemmed from the mapped partition being unable to report proper geometry to mkdosfs and apparently cluster sizes. To get around the geometry issue, I booted a dos image along with my minix system and used the old fdisk/format to create the partition.

After a few tries, I got a good partition size of 24mb that minix can read. Cluster size on the partition is 2k, anything more than that minix won't be able to use. Referring to some docs, seems minix 1.x friendly partitions can go up to 127mb.

Mounting and writing on the dos partition while the system is running didn't pose any issues, though I make sure I sync first before running dosdir.

Readme for gcc-1.37.1 on minix 1.x

Sunday, August 12, 2012

Raspberry Pi #1: First Pi

I've got my raspberry pi about a month ago, but never got a chance to play with it until yesterday. I got a great deal for a spanking new hd monitor at Accent Micro. Also borrowed some lego blocks from my son to make a makeshift case for it.

Now what to do with it? I have a webcam sitting around, might try a diy cctv. Wife's been bent on a media server though.

Finally, I discovered a community magazine centered around the rpi at http://www.themagpi.com/. Will have tons of fun reading for sure.

Thursday, August 9, 2012

Linux-0 #1: Minix

I've always wanted to hack again on the Linux kernel, especially the earliest versions. Although I remember stumbling upon a commentary and another, a remake on version 0.01 some time ago, I've thought of trying to install a Minix system myself.
The release notes for the 0.01 archive mentions Minix 1.5.10 as the version Linus used when he first developed his kernel, but it seems 1.5 doesn't play nice with the emulators I've tried. Might as well settle for the last 1.x version, and after some scratching on the head I've got a complete Minix 1.7.5 system installed on a qemu pc.
The historic Linux kernels can be found here
The Minix 1.x installers can be found here
My Minix 1.7.5 system

Random #1: Reboot

The heavy rains of this week and the accompanying power and internet disruptions provided me time to clean my work room and my archives. It has been two years since I got a lucky break and became a telecommuter. However, that also had put a stopper on my hobby research and experiments. I felt it's high time for a reboot.