Acer Extensa 355 and Slackware Linux 9.1

Because I like tinkering with old stuff (The reason? I don't have enough money to tinker with new stuff :) ), it has become a kind of sub-hobby to collect old computers and give them a new life with Linux. Especially I like old laptops, so you can imagine my joy when I was offered a pair of Texas Instruments / Acer Extensa 355's, the other in 'like new' condition, the other a bit battered, but still functional. They both had a working installation of Windows(TM) 95, which was, like, S.L.O.W. (Well, what else can you expect from 133MHz Pentium with 16 Mb memory?), but I had a hunch they would behave much better under Linux.

The better of the two machines was thus treated with a 32 Mb memory extension. Being a long-time Slackware fan, I decided to install Slackware 9.1 on this machine. I was also inspired by the Damn Small Linux -project, so I decided to do the installation along two guidelines: 1) no Qt, 2) no GTK. I wanted to know if it was possible to have a working X desktop system without using these two main (and 'bloated') GUI libraries, and the answer is a pleasantly surprised 'Yes'...

Because there isn't an internal CD-ROM drive or USB ports on the Extensa, I had to do a network install. The PCMCIA-adapter on this machine is only 16-bit, so Cardbus NIC's wouldn't fit, but fortunately I had already a SMC 8041TX-card, which worked perfectly. The network install needs 4 floppies. The images of these can be found on the Slackware installation CD: /bootdisks/bare.i, /rootdisks/install.1, /rootdisks/install.2 and /rootdisks/pcmcia.dsk. To make the floppies, insert a formatted floppy and run

dd if=PathToFloppyImage of=/dev/fd0

I had mounted the installation CD as a NFS share on my desktop machine, so after feeding the floppies to Extensa in correct order (bare.i, install.1, install.2, pcmcia) and pointing the installation program to the correct directory on the CD, the installation itself went on as painlessly as usual (Yes, I like Slackware's text-based installer :) ), if a little slowly. I chose ReiserFS as a file system, and Fluxbox as a window manager.

After booting the newly installed system everything seemed to work all right, that is, until I tried to play some music with the soundcard. That led to instant, complete hang of the machine, the only button that reacted was the power button... After that I tried everything I could think of to get the sound working, OSS and ALSA drivers, several command-line mp3-players, different ISAPNP settings, different kernel configurations... nothing. It took me a month (!) of furious head-scratching and Googleing before I finally stumbled on the answer. See the chapter "Patching" for what was amiss...

Back to the basics: a Lightweight Desktop

As I said, I was pleasantly surprised about how good a desktop system can be achieved without using any applications which need either Qt or GTK libraries. After some testing I settled on the following main applications, which are mostly either ncurses-based console applications or Motif/Xaw3d-based:

Most of these programs are from Slackware's CD, some can be found on my download page as Slackware packages, the rest are easily found either from LinuxPackages or using Google.

Patching the 2.4-series kernel for use with Acer Extensa 355 laptop

Acer Extensa series of laptops have a Yamaha OPL3SA2 sound chip and an ALi15x3 chipset. There is a DMA bug in the PCI-ISA host bridge of the mentioned ALi chipset, which, if used, causes a complete hang of the laptop. In Linux, both the OSS and ALSA modules for the OPL3SA2 sound chip use this DMA, so in order to use the sound chip in these computers a workaround for the ISA DMA bug must be enabled, which requires a kernel patch.

I found the original patch from here. For some odd reason this small patch isn't included in the standard Linux kernel, so here's my own patch for the 2.4.24 kernel. The actual patch is just an one-liner, so it is easy to add to other kernel versions, too.

• ALi chipset patch for 2.4.24

As root, copy this file to /usr/src/linux-2.4.24. Next type:

cd /usr/src/linux-2.4.24
bunzip2 ALiM1533-2.4.24-patch.bz2
patch -p1 < ALiM1533-2.4.24-patch
  

Then compile and install your kernel in the usual way (Don't forget to run make mrproper first, if you have compiled your kernel before.) And while you are at it, I suggest that you remove all the unnecessary drivers and modules from the kernel, and spend a little time optimizing it. This saves you some disc space, and more importantly, lots of compilation time. Remember, this is only a 133 MHz computer...

If all went well, on booting your new kernel you should see the following line somewhere in the output (Type dmesg | less if you lost it.):

Activating ISA DMA hang workarounds.

At last, you can start playing that ZZ Top's "Sharp Dressed Man" mp3 at full volume and enjoy the wonderful sound quality offered by the thumbnail-sized single speaker of the Extensa... ;)

Cheating the display adapter

When using Extensa with Windows(TM), you can have 65536 (16-bit) colors with 640x480 resolution (and there is a wide black frame around the display area), but only 256 (8-bit) colors with 800x600, and you can't do anything but cry about it. This is caused by the small (1 Mb) display memory of the Extensa's CT65550 graphics chip. In Linux, though, it is entirely possible to have 16-bit colors with (almost) full screen, the actual resolution being 800x590. See the resulting screenshot on the top of the page. Here's my XF86Config as an example how to do that (For XFree 4.3.0).

Other interesting links for the Acer Extensa 355:

• ALSA driver for the Yamaha OPL3SA2
• Software Suspend
• Driver for the TouchPad