Capabilities

Q. What audio formats are supported?
A. MP3 and Microsoft WMA. 3rd-party software is available to play OGG and other formats. Very-low-bitrate MP3's don't work for me (32 kbits/sec or lower). High bit-rate and variable bit-rate work OK. Note that the PMA430 does not seem to support variable bit-rate MP3 streams within AVI video files (something to bear in mind when you're ripping DVDs).

Q. What video formats are supported?
A. Microsoft AVI file format, with MPEG4 video and MP3 audio. It's not clear at present whether third-party video players (e.g., mplayer) can be made to work with the PMA430. The uncertainty is in whether these players will support, or can be made to support, the PMA's built-in decode accelerator.

Q. What image formats are supported?
A. Microsoft BMP (yeuch!), GIF, PNG, and JPEG of any size. JPEGs with monochrome (1 bit-per-pixel) encoding don't seem to work, but these are quite unusual.

Q. Why is such a small range of video encoding formats supported?
A. I don't know, but I imagine that this is because in the jurisdiction where Archos is based, selling equipment that is intended to be used to violate intellectual property law is illegal. Archos markets its video units as video recorders, and emphasises their use for recording in real time. Archos does not promote, or provide much information about, playing video files other than those recorded on the device itself. You'll notice that the PMA only plays videos encoded in the same formats it records. If the PMA could play videos in other formats, Archos could not sustain the argument that the PMA was intended for recording in real time.
      If my assessment is correct (and I'm prepared to accept that it might not be), we shouldn't look to Archos to provide support for new video formats.

Q. How is media organized on the PMA430?
A. However you like. Provided you don't mess about with the System directory (which contains the operating system), you can put media content wherever you like. As supplied, the PMA430 has top-level directories called Video, Photo, etc. You can create subdirectories under these, or create new top-level directories. Some of the built-in applications default to looking in the pre-defined directories so, although using different ones won't break the unit, it might make it slightly more fiddly to use. I believe that the MP3 library facilities in the PMA -- that organize tracks by title, album, etc. -- require there to be a directory called Music. However, many users switch these facilities off because they don't cope very well with huge media collections.

Q. Are filename extensions significant?
A. Yes. Because the PMA430 has a completely arbitrary file/directory structure, the unit relies on filename extensions to determine what to do when a file is selected to play. So it's a bad idea to give MP3 files a filename extension different from .mp3, and the same applies to the other file types supported.

Q. Can I rename the predefined directories?
A. It might be better not to -- the names of the top-level directories in particular probably should not be changed. Moreover, even changing the letter case is a bad idea. One user changed the name of /Documents/text to /Documents/Text and then found that the text editor didn't work any more. Linux, in general, is a fully case-sensitive operating system. However, it should be safe to add new directories, including top-level directories, and create new subdirectories at your discretion.

Q. Does the PMA430 support ID3 tags?
A. Yes, to the extent that you can list MP3 content by artist, album, etc. However, this feature is quite slow to use when there is a lot of installed content. In my opinion, it's better to structure your directories to group related content.

Q. How is the hard disk formatted?
A. It is a vfat (Windows 95) filesystem. Long filenames are therefore supported, but not symbolic links or file permissions. The lack of support for links and permissions is irrelevant for media storage, but is a problem for the (Linux) operating system. Consequently certain chunks of the disk are set aside for the operating system. These chunks appears as .img files when the PMA430 is mounted as an external drive. The filesystem seem by a host computer is, in consequence, completely different from the one that is is seen by the operating system from inside.

Q. How do I synchronize the PIM data with my Windows application?
A. Read the manual! Sorry, I don't use Windows, so I don't know the answer.

Q. How do I synchronize the PIM data with Linux applications?
A. The only Linux application that I am aware of that will sychronize with the PMA430's PIM data is Trolltech's Qtopia Desktop. A Linux version of this software is available from the Trolltech web site. I've never tried synchronizing over USB, but I found that synchronizing over ethernet (wired or wireless) was a no-brainer. I just entered the IP number of the PMA430 in the `Settings' page, and hit the `Sync all' button.

Q. Where does the Linux version of Qtopia Desktop store its data?
A. In a hidden directory called .palmtopcenter in the user's home directory.

Q. How can I extend the battery life?
A. Turn the screen brightness right down; shorten the screen turn-off timeout; try to avoid doing USB uploads while on battery power; turn off the wireless network adapter while you're not using it.

Q. Is the battery removable?
A. Yes; spare batteries are available from a number of eBay traders, as well as direct from Archos.

Q. How much maintenance does the operating environment require?
A. None, really. Although the PMA430 is a real computer, it isn't as configurable as a desktop computer, so there's less to break. What's more, a reboot has essentially the effect of restoring the machine to factory settings -- only the most rudimentary configuration is persistent across reboots. While this makes it almost impossible to break the software so badly that a reboot won't fix it, it does have an adverse effect on configurability (see next question).

Q. How do I configure the application launcher icons, etc?
A. You can't. Well, that's not strictly true. At the Linux level you can find the directory containing the configuration settings for the launcher icons, and hack them around using a text editor. However, all these settings will be lost if you reboot or power down the unit.
      The only settings that can be changed are those made available from the `Settings' tab of the laucher. These are written to the hard disk, and so survive a reboot. Everything else is held in volatile memory (RAM), so will be cleared on reboot.
      This strange lack of configurability is the price we must pay for having a Linux-based system that is unbreakable. Because Linux is so flexible, without measures such as this it would be too easy to get into a situation that could not be recovered without wiping the hard disk completely and starting again.

Q. How do I switch on/off the built-in speaker?
A. Click the volume control icon in the taskbar, and check/uncheck the `Use speaker' box. Note that the speaker enables itself automatically whenever the alarm sounds, so you might not to disable it again for headphone use. Alternatively, press the up-arrow key on the three-button pad for two seconds.

Q. How do I lock the buttons and touchscreen?
A. Presss the `A' key on the three-button pad for two seconds. Repeat to unlock.

Q. What conversion software is supplied?
A. The PMA430 is supplied with a freeware Windows application called VirtualDub, and a simple wrapper to invoke VirtualDub with the proper parameters for the PMA430.

Q. How well does the supplied software work?
A. It works fine, so long as the source files are in Microsoft AVI format. By default it only does single-pass encoding, so the quality will not be optimal for a given file size. You can make it do multi-pass encoding, but you have to drive it yourself. Once you get to this stage, the supplied VirtualDub wrapper won't help you much, and you'd be better or using VirtualDub directly. The supplied software won't read MPEG2 files, which is unfortunate as this is a very common format for distributing video clips. It won't read video-CD format either.

Q. What other options are available?
A. For optimum quality and speed of encoding, I suggest using transcode under Linux, which is free. This software will convert almost anything, including video-CDs and obscure formats. The only problem with transcode is that it's not terribly easy to use, even when you get to know it, which takes ages.
      The basic transcode command you need for converting an MPEG file ripped from a PAL DVD, to play on the built-in screen, is:

transcode -w [kbits] -i inputfile.mpg -y divx4 -o outputfile.avi -B 42,50,8 

• Artech's MPEG4 Direct Maker ($50)
• Pocket DIVX Encoder (free)
• Fairuse Wizard (10 € or a free version which is limited to 700 Mb)

Q. How do I rip a DVD to PMA430 format?
A. The only Windows application that I've been told will rip a DVD directly to an MPEG4 AVI file is Artech's MPEG4 Direct Maker. Otherwise, you'll need to decrypt the VOB files using something like DVD Decrypter, then run an encoder like VirtualDub or Dr.Divx on the decrypted VOBs. There are a number of freeware and inexpensive Windows utilities to decrypt VOBs. I've not used any myself, so I can't comment on which is best. Under Linux, you can use transcode to rip a DVD directly to MPEG4 like this:

transcode -w 500 -i /dev/dvd -x dvd -T NN,-1 -y divx4 -o outputfile.avi -B 42,50,8 

Q. How does recording video through the video input compare with ripping a DVD?
A. If you intend to watch video only on the built-in screen, the quality you'll get by recording through the video input is, in practice, as good as you'll get from ripping the DVD directly. In fact, unless you're showing video on a large-screen TV or video projector, the same is true for the external video output as well. What's more, unless you have a liquid-cooled supercomputer, recording from the video input is quicker than ripping a DVD with a PC, particularly if you are doing multi-pass encoding.
      There are two problems with using the video input. First, the PMA430 will cheerfully record a blank screen until its disk space runs out, so you'll have to set up a timer recording if you aren't going to be there to switch it off. Second, the PMA430 detects the MacroVision copy-protection signal on the video input, and refuses to play back the recording other than on the built-in screen. This is a major irritation if, for example, you wanted to watch a movie you recorded on the PMA430 on a hotel TV, or on a friend's TV, or even on a monitor in a different room of your own house. So, in practice, you're most likely better off ripping DVDs to MPEG4 format using a computer.

Q. What 3rd-party applications stand a chance of working?
A. In principle, the PMA430 is code-compatible with the Sharp Zaurus range, so most Zaurus applications ought to be good candidates. However, there are a number of problems with running Zaurus applications on the PMA430.

• Many Zaurus applications (especially the older ones designed for the first-generation Zaurus) try to install into bits of the filesystem which aren't writable at all. And, even if they install into locations which are writable, some file areas which were persistent on the Zaurus are volatile on the PMA430. This means that the software will disappear if you have to cold-boot the unit.
• Because the PMA430 has no non-volatile RAM, persistent application settings (such as the bookmarks in a web browser) have to be made on the hard disk. Where applications have been written to use the Qtopia environment (see below) to save persistent settings, they work properly on the PMA430, because the Qtopia implementation knows to write to the hard disk. However, applications that make assumptions about where files can be stored, and write files directly through the operating system, don't work properly.
• Many earlier Zaurus applications are hard-coded to fit the portrait screen orientation of the Zaurus. This is less of a problem for applications designed for the C7XX series, because it has a landscape screen.

Q. How much RAM?
A. 64 Mb, but only 48 Mb is available to the operating system at runtime. Presumably the rest is used for the kernel/root filesystem. [Update -- with the latest firmware, the OS now reports 64 Mb available, rather than 48 Mb].

Q. What is the hard disk capacity? How much is available?
A. The total disk size is 30 Gb. About 200 Mb is used for the OS. As supplied, a lot more of the disk is taken up by manuals, PC software, and instructional videos, but you can copy this stuff to a PC and then delete it.

Q. What is the screen size/resolution?
A. This is a tricky question. The built-in LCD screen is 3.5 inches along the diagonal, and has a fixed resolution of 320x240 pixels. However, the video overlay and image scaler -- which are used by the built-in media player and photo viewer -- have variable resolution up to 640x480. You can't see this additional resolution on the built-in screen, but you can use it with an external monitor. In practice, the video overlay resolution is adjusted in software according to the video norm (PAL/NTSC) and media resolution, and will normally be slightly smaller than 640x480.
      Ordinary Qtopia applications cannot use the 640x480 video overlay, but you can write or adapt applications to do so, using the Archos multimedia API (see below).

Q. What is the screen colour depth?
A. This is another tricky question. Ordinary Qtopia applications can use only an 8 bits-per-pixel screen layer, giving a possible 256 colours on screen at any one time. However, the video overlay provides, in principle, 24 bits per pixel -- although colour information is shared between pixels, so the `true' colour depth is somewhere between 16 bits (approx 65,000 colours) and 24 bits (approx 16 million colours). The overlay is accessible through the Archos multimedia API, and this issue is discussed in more detail in the `multimedia SDK' section.

Q. What external interfaces are there?
A. USB host port (for connecting keyboard, etc), USB device port (for connecting the unit to a host for upload/download), composite video in/out, stereo audio in/out, S-video in (but no out), wireless network adapter, infrared transmitted and receiver. There is no external PCMCIA slot, nor an external memory card slot. The aperture in the case that housed the memory card slot on the AV420 is blanked off on the PMA430.

Q. Is there any non-volatile RAM?
A. There does not appear to be. With a built-in hard disk, it is of doubtful value.

Q. What about bluetooth?
A. There is no built-in bluetooth adapter. However, there is a full driver stack for supporting a USB bluetooth dongle. In principle, any standards-compliant USB bluetooth dongle should work if you plug it into the PMA's USB host port. The problem is that many USB bluetooth gadgets claim to be standards-compliant but, in reality, require firmware to be downloaded using a Windows-only downloader. So they are only standards-compliant if you're running on Windows, which is almost a contradiction in terms. Anyway, if you can get hold of a good USB bluetooth dongle, it should work, in that there is driver support.
      This is all very well but -- so far as I can tell -- none of the PMA's built-in applications are bluetooth-capable. So I'm not sure what you'd do with your bluetooth adapter even if the PMA supported it. In due course we might see 3rd-party application with bluetooth capabilities, but I wouldn't hold your breath.

Q. Can you connect an external hard drive/CDROM?
A. It would appear to be possible to connect an external USB disk drive or CDROM. Although I've not tried it, all the drivers are in place.

Q. What about firewire?
A. There's no hardware or drivers, so probably not :).

Q. Which external keyboards are supported?
A. Any USB keyboard can be connected to the USB host port, using the adapter provide with the PMA430 (the adapter is necessary because the PMA430's host port is a miniature USB socket, while USB keyboards tend to have full-sized plugs). On most USB keyboards, the F2, F3, and F4 keys take on the same functions as the three-button pad on the PMA itself, while the arrow keys, enter, and escape mirror the six-button pad.

Q. What about an external mouse?
A. Yes, there are drivers for a standard USB mouse, and also for a number of digitising tablets!

Q. How do I make Qtopia (user interface) recognize an external mouse?
A. In the console, execute the following command (note -- case sensitive)

qcop 'QPE/System' 'setMouseProto(QString)' 'IntelliMouse:/dev/input/mice'

qcop 'QPE/System' 'setMouseProto(QString)' 'AVPanel'

Networking

Q. What is the range of the wireless ethernet?
A. About 10 metres in air with a good quality access point. I have heard reports of 50 metres out-of-doors. In my house, which is tall and thin, the wireless range will just work from the ground floor to the attic, but it's not very fast. The range will almost certainly never be as good as that which can be achieved by something that has an external antenna. I've asked Archos why they don't supply an external antenna, or a place to connect one, and it appears that the device is so crowded inside that there isn't space to run the connections from the RF receiver to the outside of the case!

Q. Does the network adapter enable itself automatically when using a network-aware application?
A. Not as far as I can tell. You have to switch the network adapter on using the network applet in the taskbar. I suspect that this is because the PMA430 supports multiple network interfaces, and it doesn't want to guess which one to use.

Q. What about IEE802.11g (fast wireless ethernet)?
A. Hmmm... probably not; at least, not yet. You could plug in a USB wireless dongle, but I doubt that drivers would be included. Few of these devices have Linux drivers even for desktop Linux versions. What you could do is connect the PMA to a (wired) ethernet-to-wireless media converter (like the ones you can buy for games consoles), via a USB-ethernet converter (see below).

Q. How does the PMA430 support wired ethernet?
A. There is no built-in ethernet port. However, you can connect a wired ethernet dongle to the USB host port. Archos supply a suitable dongle, but it's quite expensive. Most of these devices are based on the RealTek RTL8150 chip, and there is a driver for this provided with the PMA430. You can get a suitable device from eBay for about $5. I don't know what other devices, apart from those based on the RealTek chip, have driver support.

Q. Does the PMA430 support auto-configuration of IP parameters?
A. Well, it supports DHCP so, to that extent, yes it does. It also supports autoconfiguration with PPP over dial-up connections. However, it's a bit of a drag to get the IP number once a connection is established, and you'll need the IP number if your want to sync PIM data over the network. So you might want to define a network connection with fixed IP parameters if your environment allows for this.

Q. How does IP over USB work?
A. IP over USB is a point-to-point IP connection between two devices. If you want to establish a private network connection between the PMA430 and a PC/workstation, you can use IP over USB to achieve this over the ordinary USB connection. However, there are a number of problems with this. First, not all PC operating systems support IP over USB, and it tends to be fiddly to configure even on those that do. Second, you have to start the connection on the PMA430 and then hurriedly plug the USB cable in and then start the PC end. If you plug the USB cable in first, the PMA430 automatically switches to `USB drive' mode. Since you can get a USB-ethernet dongle for $5, it's hard to see why IP over USB would be much use on the PMA430 and I, for one, don't use it routinely.

Q. What is involved in getting dial-up to work?
A. So far as I can tell, the PMA only supports dial-up over infra-red. In principle, dial-up over serial should work via a USB-serial converter, but (a) there is no option for this in the network configuration application, and (b) there do not appear to be any drivers installed for USB-serial converters. So, in short, you're going to need an infra-red modem, e.g., a cellphone. I've tried the dial-up networking with my Nokia 6310i, and it worked fine. The trick with this phone is that you must enable the IR receiver immediately before trying to establish a connection. The receiver switches off without warning if it thinks the phone is idle. For what it's worth, my Nokia is on UK Vodafone, and to get a GPRS connection via dial-up I enter the phone number `*99#'. This only works if you have a dial-up GPRS subscription; if you don't, you'll have to use an ISP telephone number. If you use GPRS, you'll have to use the GPRS provider's SMTP server to route outgoing e-mail, even if you use an ISP's POP/IMAP for incoming mail. This is because most ISPs either reject SMTP traffic from IP numbers other than their own, or enforce SMTP authentication (which is not supported -- see below). For UK Vodafone, the smtp server is send.vodafone.net.

Q. What is the Web browser?
A. Opera 6. It's a perfectly serviceable browser and, with a wired ethernet connection, works surprisingly quickly. With a wireless connection the limiting factor is likely to be the network speed in a lot of cases.

Q. What are the capabilities of the e-mail client?
A. The built-in client supports plaintext (that is, unencrypted) POP, IMAP, and SMTP. It allows multiple accounts, and outgoing and incoming server can be different in each account. There is no support for authenticated SMTP, either plaintext or encrypted. This is rather unfortunate, because ISPs are increasingly requiring mail clients to authenticate before sending mail -- no ISP wants to be turned into a spam relay. I've been told that TheKompany is working on a more sophisticated mail client for the PMA [update -- just released :)].

Q. What about telnet, FTP, etc?
A. There is no built-in support for any of these, either clients or servers, except what is available in Opera. However, I have compiled some standard Linux networking apps using an ARM cross-compiler (see below), and they work fine. Oddly enough, the PMA430 is configured to accept incoming telnet connections on port 23, but there is no telnet server available to handle the connection. This is very odd -- I can only imagine that at some point in the past the PMA430 was intended to have a telnet server, perhaps for debugging. [Update -- in the latest firmware, this `feature' has been removed]

Q. Which Linux distribution is it?
A. Undocumented. It is very similar to Lineo Embedix, as used in the Sharp Zaurus range of PDAs. Some Zaurus applications install and run without modifications.

Q. What is the kernel version?
A. 2.4.19. It's a reasonably complete build, even including kernel modules to support hardware that isn't included with the base product.

Q. What standard Unix utilities are provided?
A. The basic Unix commands -- cp, rm, etc. -- are provided; these are supplied by the BusyBox project. With BusyBox, all the standard commands are provided in one executable, to save space. There is also any implementation of rsync, which can be used to synchronize whole filesystem with a remote rsync server (e.g., on a PC).

Q. What is the user interface?
A. Qtopia (v1.7), provided by Trolltech. Qtopia is a user interface and program manager derived from Trolltech's `Qt' graphical user interface library. Qt is widely used by Linux developers to provide a graphical interface for their applications, and it's not too difficult to convert desktop Qt applications to run on Qtopia, provided they aren't too demanding of resources. For example, there is a Qtopia version of the Konqueror web browser, which was developed using Qt for desktop machines.
      However, Qtopia is not an extension of the X11 windowing system. Linux X11 applications will not run under Qtopia, even if they are compiled appropriately and supplied with all the necessary libraries. In a sense this is a shame, since there are thousands upon thousands of X11 applications, none of which will be easy to make work on the PMA430. In another sense, X11 was never intended to run in the resource-constrained environment of a PDA, and Qtopia will be much faster. You probably could run XFree86 -- the standard Linux implementation of X11 -- on the PMA430 with a bit of fiddling about. However, all the built-in applications, including the PIM applications and the media players, are Qtopia applications, so you might be shooting yourself in the foot by doing this.

Q. How is the filesystem organized?
A. In a very convoluted way, because there are two severe constraints on the filesystem implementation. First, the unit as a whole must look like a DOS/windows disk when it is emulating a USB hard drive. Otherwise it wouldn't work with Windows systems. Second, the basic Linux filesystem must be read-only, so the user can't break it too easily.
      To satisfy these constraints, the Linux root filesystem, along with the kernel, is found in single, large file called aimage.img within the Windows filesystem. The bootloader knows how to locate this file, load the whole thing into memory somewhere, and boot the kernel, with the image file mounted read-only as the root directory. During the boot process, the Linux system init script mounts the whole hard disk on the /media directory (which means, of course, that the root filesystem includes itself recursively, but it's as well not to think too hard about that).
      Then the init script locates the file progfs.img which now appears within the /media/System directory, and mounts it as a loopback file on the directory /progfs. This is where the package manager will install 3rd-party applications (and also where the Opera browser lives). Then the init script mounts a RAMdisk on /opt/Qtopia, and creates a whole heap of symbolic links from within this directory to read-only locations. It also symlinks all the configuration directories within /progfs/opt/Qtopia, which is how 3rd party applications remain visible in the launcher after a reboot, even though the launcher configuration (in /opt/Qtopia/apps) is volatile.
      So, when mounted as an exernal drive, the filesystem looks as follows:

Hard disk (vfat format)
  Video/
  Music/
  Photo/
  pda/ (all the PIM files and system config goes here)
  System/aimage.img --> mounts on / under Linux
  System/progfs.img --> mounts on /progfs under Linux 

/ (read-only mount of /System/aimage.img)
  etc/ (ramdisk, lots of links to...)
  etc.rom/
  usr/...
  opt/Qtopia/ --> (ramdisk, lots of links to...)
  opt/Qtopia.rom/ (ramdisk)
  tmp/ --> (ramdisk)
  var/ --> (ramdisk)
  media/ --> (whole hard disk, vfat)
    Video/
    Music/
    Photo/
    System/ 
  pda/ (all the PIM files and system config goes here)
  progfs/ (read-write mount of /System/progfs.img) 
    opt/
      Qtopia/
      QtPalmtop/
      ...

Q. Where can I get a C/C++ cross-compiler?
A. It's worth bearing in mind that anything which produces executables which run properly on the Sharp Zaurus will almost certainly work for PMA430 development as well. The Lineo ARM port of GNU C/C++/glibc for Embedix produces code that works fine on the PMA430. This is available for Linux and Windows, but I've only used the Linux version. You could use other ARM cross-compilers, but you'd still be faced with the problem of obtained Embedix-specific headers and libraries. I don't believe there is an `official' source of the Embedix SDK any more. If you do a Google search for `embedix zaurus cross-arm' you'll probably turn up a few likely locations. It is now also available from the Archos website.
      Embedix was originally produced by Lineo, which is now part of Metrowerks. Metrowerks continues to produce a Zaurus development tool as part of its Code Warrior product. I've not used it, so I don't want to comment on it.

Internationalization

Q. What character sets does the PMA430 support?
A. Qtopia is at least partially unicode-aware. This means that text entered in the built-in applications is managed and stored in a multi-byte format, so that a large number of characters can be represented. The unicode standard currently defines over 15,000 different symbols -- enough for most of the world's languages.
      However, having the ability to store a large number of characters is not much use unless you have also an ability to enter and display them (more on this below).
      Qtopia's unicode-compliance is not perfect. I have noticed, for example, that although the Contacts application can store and display Japanese names in kanji, the characters are not rendered correctly in dialog boxes. It's also worth bearing in mind that, if you synchronize the PMA with a PC or workstation, there's no guarantee that the software you use to synchronize, or to manage the data, will be unicode-aware, or that you have the fonts necessary to display the characters. Qtopia Desktop is unicode-aware, provided your platform has full unicode fonts. I couldn't comment on any other software.

Q. What must I do to get the PMA430 applications to display non-western characters properly?
A. So far as I know, the only built-in font that supports a relatively full set of non-western characters is unifont. You can select this from the `Appearance' tab in the launcher. Characters for which there is no font symbol display as boxes.

Q. How do I enter non-English (but west-European) text?
A. If you are writing extensively in French, German, Spanish, or Italian, or a language with similar characters, language, you might wish to consider setting the default language of the PMA accordinging. This will change the layout of the virtual keyboard, and expose more of the characters used by those languages. Otherwise, if you just want a few non-English characters, you could use the unikeyboard `input method', as described below.

Q. How do I enter non-western text?
A. This is quite tricky. It is mildy irritating that the PMA supports non-western characters for display and data storage, but provides absolutely no way to enter them. What is required for stylus-based text entry is an `input method' (Qtopia jargon) which supports the language(s) you want to use. If you only use a few non-western characters occasionally, you might get by with unikeyboard (see below). Otherwise, you could try one of the numerous Zaurus input methods that are available. You'll need to overcome the problem that there is no way to install a new input method through the graphical user interface but, apart from that, Zaurus input methods should work OK.

Q. Why does the touchscreen stop working after waking the PMA up from sleep mode?
A. I don't know, but this problem only seems to afflict units with the earliest firmware. A firmware upgrade (from the Archos website) should fix it.

Q. Why can't the PMA's wireless network adapter connect to my access point?
A. The most obvious answer is: because it's out of range. The PMA has no external antenna, so its wireless range is not as great as that of a laptop PC, for example. However, even if the AP is in range, people often experience problems, especially with WEP-encrypted networks. I have a suspicion that the problem with WEP lies partly in the way APs and devices convert textual keys (passwords) into numbers. At the protocol level, a WEP key must be either a 40-bit binary number or a 128-bit binary number. These bit sizes can be represented as either 10 or 26 hexadecimal digits, or 5 or 13 textual characters. The problem is that the key size must be exactly 40 or exactly 128 bits, so if the key size you enter in the AP or the device is not of the right size, it has to be padded. I'm not convinced that different products all pad the same way. So, for example, if you enter `fred' as the WEP key in your AP, and the selected key size is 128 bits, your four characters have to be padded to 13 characters. The AP might do this by padding with spaces at the beginning, or at the end, or repeating the characters. Provided all your wireless equipment comes from the same vendor, you probably won't have a problem, because all the equipment will pad the key the same way. However, there's no guarantee that the PMA will follow the same convention.
      In short, the best way that I have found to ensure that wireless equipment from different vendors works properly together is to use a key that fills the bit size exactly. So, because I'm using 128-bit keys, I would always enter a 26-digit hexadecimal number on all the equipment in the building.
      I appreciate that this is of no help if the access point is beyond your control -- in an airport or something. But if it doesn't work there, the problem does not necessarily lie with the PMA, but with the lack of standardization in this area within the networking industry.

Q. Why can't I connect to a network using my USB ethernet adapter?
A. The PMA only has drivers for a limited range of USB ethernet adapters. Most obviously, it supports the device that Archos sells; it should support other devices based on the RealTek RTL8150 chip; for other devices, your mileage may vary. The problem is that it can be very difficult to tell, before making a purchase, what chip your prospective device is based on.

Q. My PMA gets warm in use -- is this normal?
A. I don't know if it's normal, but it's undoubtedly typical. You should expect it to get warm to the touch, especially with the wireless network adapter in use.

/opt/PMA400//lib/libcsl.so: undefined reference to 
    `QExclusiveLock::unlock(QExclusiveLock::Type)'

Q. How do I write directly to the video framebuffer?
A. There are two basic approaches: using the ordinary Linux framebuffer interface (at /dev/fb0), and using the Archos framebuffer API. The former is probably preferable if you are porting existing Linux applications, but (so far as I can tell) you won't get more than 8-bit-per-pixel (bpp) pseudocolour that way.

Using the Linux framebuffer
The basic approach is to open /dev/fb0 as a random-access file, then write pixel data directly to it. The resolution of the PMA screen is 320x240 when addressed this way, so /dev/db0 appears as a file 76800 (=320x240) bytes long. The first 320 bytes is the first screen scan line, the next 320 bytes is the second, and so on. You can use the mmap() function to map the whole framebuffer into your application's memory, and just address it like a 320x240 byte array.
      The usual way of configuring the Linux framebuffer driver is by way of ioctl() calls. I have found that many of these calls are unimplemented by the Archos driver, so some experimentation may be needed.

Using the Archos framebuffer API
The framebuffer API treats the screen as three overlapping layers. The top layer is the standard Linux framebuffer, onto which the usual elements of the graphical user interface are drawn -- menus, buttons, etc. This layer has a fixed resolution of 320x240 pixels, at 8 bpp. It is this layer you are drawing on when you write to /dev/fb0 as discussed above. All the standard QT graphics API calls write on this layer as well. In normal circumstances (that is, running ordinary Qtopia applications), the two underlying layers are not even visible. I shall refer to this layer as the `QT layer'.
      Below the QT layer are two variable-sized video layers. Only one of these is accessible through the Archos SDK (so far as I can tell). Despite what it says in the Archos documentation, the default resolution of the accessible layer is 640x240 (not 640x480). In order to use video layer, you must make the QT layer transparent, so that the video layer can show through. In the simplest case, you can create an application with a QMainWindow as its main widget, and set the background colour to QColor(0xFE, 0, 0xFF). So, the outline of a trivial application might look something like this:

int main(int argc, char** argv)
  {
  QPEApplication a(argc, argv);
  QMainWindow mainwidget;
  mainwidget.setBackgroundColor(QColor(0xFE, 0, 0xFF)));
  a.showMainWidget(&mainwidget);
  while (...)
    {
    // Write to video layer
    a.processEvents(); // Allow Qtopia to carry on working!
    } 
  return 0;
  }

#include <coprocinterface.h>
#include <aresourceset.h>

// Reserve the video hardware for this app
AResourceSet* ars = AResourceSet::get();
ars->reserve(ars->ResImageResizer |
  ars->ResDSP | ars->ResSDRAM);

// Get a reference to the video processor
CoprocInterface *cpi = CoprocInterface::get();

// Get a reference to frame(0), which is the one actually
//  in the display
unsigned long vfoZero = cpi->videoFrameOffset(0);

// Create a buffer of pixel data of the appropriate size
//  (640x240 if the framebuffer is left at default settings)
unsigned short int buff [...];

// Put the pixel data in the buffer
buff[0] = ...; buff[1] = ...;

// Dump the buffer to video memory
cpi->writeVidMemory (vfoZero, buff, sizeof (buff));

Q. How do I use the hardware image scaler to expand/reduce images to fit the screen?
A. The simplest way, I think, is to build your image in one of the un-displayed memory regions in the video processor, then use the ImageScaler class to both scale it and transfer it to the display region.

#include <imageresizer.h>

ImageResizer *scaler = ImageResizer::get();
unsigned long vfoZero = (unsigned long)cpi->videoFrameOffset(0);
unsigned long vfoOne = (unsigned long)cpi->videoFrameOffset(1);

//... use writeVidmem to write to vfoOne, as described above

// Set the sizes of the source and destination areas
int srcWidth = ..., srcHeight = ...;
int destWidth = ..., destHeight = ...;

QSize srcImageSize (srcWidth, srcHeight);
QRect srcWindow (0, 0, srcWidth, srcHeight);
QSize dstImageSize (dstWidth, dstHeight);

//... scale and copy from vfoOne (offscreen) to
//    vfoZero (onscreen)

scaler->blitImage (vfoOne, srcImageSize,
    srcWindow, vfoZero, dstImageSize); 

Q. Which pixel format (colourspace) does the PMA430 use?
A. The PMA430 video layer uses YUV422 format (also known as YUYV). This gives 24 bpp colour resolution with 16 average bits per pixel. This seemingly-miraculous feat is by sharing the chroma data between pairs of pixels. In YUV422, the display is made up of 32-bit (4-byte) `megapixels', where each megapixel represents two screen pixels. The format of each megapixel is as follows:

1st byte: luminance of first pixel in the pair
2nd byte: U-chrominance of both pixels
3rd byte: luminance of second pixel in the pair
4th byte: V-chrominance of both pixels