faq.txt

rockbox掌上游戏机源码,包括pc仿真和小机代码

Q1. What is a FAQ?
A1. A rare small animal of the species 'Textius Electronicus'. It is known for
    its helpful attitude and vicious misspellings.

Q2. Okay, fine, what is _this_ FAQ?
A2. This FAQ is for questions (that we have answers to) that have been asked
    repeatedly either in emails or on IRC.

Q3. What is Rockbox?  What is it's purpose?
A3. The purpose of this project is to write an Open Source replacement 
    firmware for the Archos Jukebox 6000, Studio 20 and Recorder MP3 players.

Q4. I want to write code for my Archos, how do I proceed?
A4. Our guide on first time (http://www.rockbox.org/docs/firsttime.html) 
    Rockbox development should answer most of your questions.

Q5: What is CVS?
A5: Concurrent Versions System (http://www.cvshome.org).  We have a small
    help page about how to use this to get, update and commit files on the web
    at http://www.rockbox.org/cvs.html

Q6. What exactly is the CONTRIBUTING file? 
A6. Just like the name implies, it lists conventions that the project follows, 
    and in turn asks you to follow, for the formating of source code in
    general.

Q7. Okay, so I read CONTRIBUTING and although I don't agree with all your 
    conventions, I am going to be sensible and follow them anyway.  Now what?
A7. Start by reading up on the information about the jukeboxes on our web page.
    Then go into CVS and look at the code we've written. Then take what you
    need and start writing.

Q8. I want to join the development team, but don't have a SourceForge account,
    what should I do?
A8. You don't need a SourceForge account to help developing Rockbox. Just
    submit patches (http://www.rockbox.org/twiki/bin/view/Main/WorkingWithPatches)

    If your patches are consistently well-written and thus accepted, you may
    ultimately be offered CVS commit access. If that should happen, you will
    need to get a Sourceforge account:
    http://sourceforge.net/account/register.php

Q9. Do you have a mailing list?
A9. Sure do!  As a matter of fact, we have several of them for specific things.
    Please check out: http://www.rockbox.org/mail/, and please see FAQ entry
    75.

Q10. Great you have a mailing list!  Is there anyway for me to catch up on
     past posts?
A10. Check out the archives at: http://www.rockbox.org/mail/

Q11. How can I meet the developers working on the project?
A11. One way is by visiting us on IRC.  Head on over to the server
     irc.openprojects.net, and then join "#rockbox".  There is usually at 
     least one person there.  If you don't see any activity, feel free to post 
     questions anyway, several of us log the channel and will get you answers
     when we unidle.

Q12: Wow, you guys talk on IRC a lot?  I wish I had been around for those 
     conversations to see what happened.
A12: We are glad you mentioned that!  http://www.rockbox.org/irc happens
     to have a list of various logs we have recorded of events in the channel.
     Feel free to read up, and ask questions on what you find.

Q13. What is this "SourceForge" you keep mentioning?
A13. http://www.sourceforge.net

Q14. Can the changes or the software that Rockbox suggests or offers 
     possibly damage my Archos Player?
A14. All firmware mods that are presented are still highly experimental. 
     Try them at your own risk. We offer no guarantee that this software, or 
     the hardware modifications we show, will not damage your player or void 
     your warranty.  That said, we have not been able to damage any of our 
     units by modifying only the firmware. You can accidentally password 
     protect your hard disk, but there are ways around that. (See below.)

Q15. I want to see what the inside of my player looks like, but I would really
     like to avoid voiding my warranty.  Is there anything you can suggest?
A15. We have a collection of photos of both the player and recorder. Look at
     http://www.rockbox.org/internals/

Q16. What exactly are you trying to achieve with this line of development?
     (A.K.A. what's your purpose for being here?)
A16. Firstly, we wouldn't start something like this if we didn't simply enjoy
     it profusely. This is great fun!
     Secondly, we feel the original firmware is lacking some features and
     contains a number of annoying bugs that we don't want to live with.

Q17. You mention supporting Ogg Vorbis and other file types on your list of
     ideas. What is the status on that?
A17. Pessimist's Answer: At the current time we believe this is not very
     likely. The Micronas chip (MAS3507) decoder in the Archos does not
     natively support decoding and there is very little program space in the
     player to implement it ourselves.  The alternative would be to write a
     software decoder as part of the Rockbox firmware.  However, as much as we
     love our players, the computing power of the Archos (SH1 microcontroller)
     is not fully sufficient for this need.

     Optimist's Answer: We can play any format if only we can write code for 
     the DSP to decode it.  The MAS 3507 (and 3587) are generic DSPs that 
     simply have MP3 codecs in ROM. We can download new codecs in them and 
     we will be the first to celebrate if we can get OGG or FLAC or anything 
     into these DSPs. Unfortunately, we have no docs or tools for writing new 
     MAS DSP code and Micronas is very secretive about it.  If anyone can 
     help, please get in touch!

     The recent release of Tremor (integer Ogg decoder) indicates it uses
     around 100 KB for lookup tables. That's not unreasonable for a decoder,
     but we only have 4 KB for both code *and* data. So the grim reality is
     that Ogg will never be supported by the Archos Players and Recorders.

Q18. What about supporting playing of WMA files?
A18. Dear Mr. Gates, you have two options.  Re-read previous question, or go 
     buy your own project.

Q19: But you don't understand, I'm not talking about decoding here, 
     since the data we want may already be in the decoded format (PCM). 
A19: Okay, last time.  No.  We have no problems whatsoever reading different 
     file formats, call it PCM, WAV, GRI, PQR or whatever.  The problem is 
     that the CODEC only accepts MP3 data and nothing else. We could write a 
     new CODEC if we knew how to do it, but there is no documentation on the 
     DSP. Please note that we have no access to the DAC, so we can't send the 
     data directly to the DAC.

Q20. What is the most recent version of Rockbox?
A20. We recently released version 2.3, so head on over to
     http://www.rockbox.org/download/ and pull it down.
     Make sure to read the release notes.
     (http://www.rockbox.org/download/rockbox-2.3-notes.txt).

Q21. What do you plan to add to coming versions?
A21. We don't plan versions in detail. We just write code, and when it feels
     right we release a new version.

Q22. I tried one of your firmware files and now I can't access my hard disk!
     When I turn on my jukebox, it says:
                     Part. Error
                     Pls Chck HD
A22. Your hard disk has been password protected. We're not 100% sure why it
     happens, but you can unlock it yourself. Look at:
     http://www.rockbox.org/lock.html

     Note: This is a very rare problem. Most people who think they have a
     locked disk actually just experience hardware and/or driver problems.

Q23: This FAQ doesn't answer the question I have.  What should I do?
A23: You have a couple options here.  You could forget the question, find an
     easier question, or accept '42' as the answer no matter what.  We don't
     really recommend any of these (though I do opt for '42' often myself).
     What we do recommend is stopping by IRC, visiting the web site
     (http://www.rockbox.org) to see if the question was answered else where
     (like our nodo http://www.rockbox.org/twiki/bin/view/Main/NoDo FAQ)
     and just not included here, or ultimately dropping an email to the
     mailing list ([e-mail]) or the FAQ maintainer listed on the
     project home page.

Q24: Are there other ways to contact the developers?
A24: Yes.

Q25: Are you going to tell us what they are?
A25: No.  Post to the mailing list and we will get back to you.

Q26: But I _really_ want to talk with you in person.
A26: I'm sorry.  My girlfriend/boyfriend/pet says I'm not allowed to, and the
     doctors here won't let me have pens or pencils.  They say its some rule
     about us not having sharp objects.  I'm sorry.  Now please stop calling
     me here.

Q27: Will you ever port Quake II to the Archos?
A27: If you ask that again, I'm sending your address and phone number to the 
     guy that mailed us with question #24.

Q28: Umm, was that sarcasm?
A28: That's it, I'm mailing him now.

Q29: Is this legal? I mean, I'd just hate to see something like that 
     challenged under the DMCA in all its ridiculousness. Any thoughts or 
     ideas?
A29: We believe we are in the green on this.  We are not violating anyone's
     copyright and we are not circumventing any copy protection scheme.
     This has been a big point for the project since its inception.  Some 
     people wanted us to distribute patched versions of the original firmware,
     but seeing as that _would_ have violated Archos' copyright, we didn't 
     follow that course of action.

Q30: On the web site [and various information postings] you state 
        "Every tiny bit was reverse engineered, disassembled and then 
         re-written from scratch".  
     If it was rewritten from scratch then why was it first reverse-engineered
     and disassembled? Instead this sounds more like someone disassembled it
     then used the understanding that they gained to create a new version,
     which is not quite the same as "from scratch". 
A30: Don't confuse the terms.  Reverse engineering means examining a product 
     to find out how it works.  Disassembling the firmware is merely one tool 
     used in that examination.  Oscilloscopes and logic analyzers are other 
     tools we have used.  We have written every single byte of the Rockbox 
     firmware. But we could not have written the software without first 
     researching how the hardware was put together, i.e. reverse engineer it.
     All of this is completely legal.  If you define "from scratch" as writing
     software without first researching the surrounding interfaces, then no 
     software has ever been written from scratch.

Q31: This FAQ is great, but do you have anything with a bit more detail?
A31: Check out our website and it's documentation.  Rockbox also has a user
     manual you can read.  http://www.rockbox.org/manual/manual.pdf

Q32: I've heard talk of a 'Rolo'.  What is that? (Or 'All you ever wanted
     to know about Rockbox boot loaders')
A32: Rolo is our bootloader.  Rolo became available with our 1.4 release.
     To make use of Rolo, you must have a file with the same extension as 
     your Rockbox firmware (.ajz on Recorder, .mod on Player) but a different
     name.  You can then browse to it, and you 'run' the other firmware
     you wish to switch to by pressing play. Remember to set the Show Files
     option to "Supported" or "All" to be able to see the firmware files in
     the browser.

     *Poof* You will reboot to that firmware.  (Note that in order to return
     to Rockbox you may need to reboot manually if the new firmware you loaded
     does not have a bootloader itself.)

Q33: Can I use the Archos as an USB hard disk to store data from my PDA/
     digital camera/phone etc.
A33: No.  See http://www.rockbox.org/twiki/bin/view/Main/NoDo#4_Interfacing_with_other_USB_dev

Q34: When I use Rockbox my jukebox's red "error" light turns on a lot, but this
     doesn't happen on the factory firmware.  Why?
A34: Rockbox uses the red LED as harddisk activity light, not as an error 
     light. Relax and enjoy the music.

Q35: I have a question about the batteries...
A35: STOP!  We have put together a completely different FAQ for battery 
     related questions.  
     Check out: http://www.rockbox.org/twiki/bin/view/Main/BatteryFAQ

Q36. I have a question about patches...
A36. Check out http://www.rockbox.org/twiki/bin/view/Main/WorkingWithPatches
     as it should answer any patch related questions you may have.

Q37: What is the WPS?
A37: That is the 'While Playing Screen'.  Basically this is what is shown on
     your player's display while we are playing your song.

Q38: What good is the WPS?  How usable/flexible is it?
A38: It is very good if you want information about the current item playing ;)
     By using a WPS configuration file you can manage exactly how/what you 
     want displayed on your Archos Player.  (Even better yet, if you want 
     a feature that's not there, we are _always_ open to suggestions!) 
     Please see http://www.rockbox.org/manual/wps.html for information.

Q40: So how do I load/make a .wps file?
A40: You check out http://www.rockbox.org/twiki/bin/view/Main/CustomWPS
     to learn the format/features of a .wps file, and read the manual to
     learn how to load it ;)

Q41: Does Rockbox support other languages? How do I load/use different 
     languages?
A41: See: http://www.rockbox.org/lang