The Archos Angstrom Improvement Project

This is a project to create a version of Angstrom Linux that integrates better with the Archos 5/7 hardware and is generally more useful and stable than the version supplied with the SDE. The SDE version is only really a proof-of-concept, and little work was done beyond that which was necessary to get the unit to boot to a desktop.

The project has three basic deliverables, each of which shared, to some extent, with other Linux implementations that might be used on the 5/7.

• A Linux kernel
• An initial ram filesystem (initramfs)
• A root filesystem

At present the kernel is essentially unmodified from the basic SDE distribution. The initramfs has been significantly extended to allow root filesystem locations to be specified in places other than the original SDE default, and to allow the user to select from alternative root filesystems at boot time. The root filesystem is based on the GPE desktop, but with extensive additions and fixes.

If you have the time and patience, you can built the entire system yourself from source, as described here. Alternatively, prebuilt binary images are available from

 http://www.openaos.org/~kevin/

For more information about the binary distributions, please see here. For current bugs and feature requests, see here.

Related pages:

• USB file sharing in Archos Angstrom
• WiFi networking support in Archos Angstrom
• Filesystem organization and layout

What works

• Power management is now reasonably functional. The unit can suspend to RAM in most circumstances, and wake correctly more often than not. The screen blanks (and, in fact, the entire display is shut down to save power) when the unit is idle, and can be configured to suspend after a certain idle period. The disk will spin down when it is not in use. Applications can plug into the power management daemon (see below) and request different power management modes (e.g., a video player can prevent the screen blanking). The battery charge level is reported. although there is still some work to do in that area.

• The basic GPE desktop, and the Matchbox window manager, are mostly useable. Most of the irritating touchscreen glitches and over-sensitive virtual keyboard repeats have been sorted out. Some of the GPE utilities have been plumbed into the power management system. So now the batter charge status is reported and the backlight brightness slider works as it should. It doesn't sound like a big deal, but a mobile device is largely useless if you can't keep track of the battery charge level.

• WiFi networking works in at least some setups, and there is a rudimentary user-level configuration utility. Before trying to use this feature, please read this -- there are some things users need to watch out for.

• Files can be shared over USB with a host computer. Sharing can be enabled and disabled using a GUI. Unlike in AVOS, connecting a host computer to the USB port does not suspend normal operation. The downside of this arrangement is that we have to dedicate a specific area of storage for sharing. For more information on the USB support, see here.

• At least one media player -- mplayer -- is useable. The mplayer user interface is not particularly elegant, and a more touchscreen-friendly alternative needs to be sort (or developed), but you can play music and at least some movies.

• There are graphical interfaces for controlling the screen (brightness, contrast, gamma) and audio (EQ, 3D effect, speaker) as well as power management settings.

• The boot manager (really root filesystem manager) works. You can supply a menu file containing a list of root filesystem images and there locations. The user interface is touch-screen enabled (although there is still some work to do here). It is capable of booting the original Archos AVOS firmware if it is installed, as well as Angstrom Linux. However, there are legal complexities here -- this firmware is proprietary, and we can't distribute it.

What doesn't work

• It's unlikely that an Angstrom-based system will ever have video support to compare with that in the standard Archos firmware. This uses hardware decoding, based on a DSP system that is proprietary.
• There is no support for external video or external digital audio.
• There are many small bugs and irritations

The archos-helper hardware management daemon

archos-helper is a unified hardware management daemon for the A5/A7. It handles power management including the hardware-specific parts of suspend-to-RAM, idle detection, screen management (brightness, contrast, backlight), audio hardware (EQ, effect, speaker), and monitors the hardware buttons. It then provides access to the hardware to other applications over a simple socket protocol. The protocol is encapsulate in a C API, although there's nothing to stop other programming languages being used. One of the applications that uses the library is the archos-helper GUI, which by default pops up when the power button is pressed. See screenshot below.

Future work

• Improvements to the overall look-and-feel of the Matchbox window manager, or even the adoption of a different window manager altogether
• An improved media player, or improved interface to mplayer.
• Bluetooth support, perhaps with a view to supporting 3G wireless, etc
• An improved on-screen keyboard

And last, but not least:

• There are still many bugs to fix, both in the basic Angstrom/GPE code and in the new code developed for this project :/