AXN100@psuvm.psu.edu (12/02/90)
I have a Pioneer (sp) 6pack player. On the back there are two
pin-outs for a receiver to take control of the player. I was wondering
if there was anyway for me to use these pin-outs to let my amiga take
control of the CD player; thereby, making it into a CD-ROM jukebox.
Just Radom thoughts
Ajaixanthian@zorch.SF-Bay.ORG (Kent Paul Dolan) (12/02/90)
In article <90335.112615AXN100@psuvm.psu.edu> AXN100@psuvm.psu.edu writes: > I have a Pioneer (sp) 6pack player. On the back there are two pin-outs > for a receiver to take control of the player. I was wondering if there > was anyway for me to use these pin-outs to let my amiga take control > of the CD player; thereby, making it into a CD-ROM jukebox. I'm no world class expert on CD-ROM, so take this with a grain of salt. Both digital CD-ROM and audio CDs use binary data on the media, in the sense that it is either on or off, with no intermediate states. However, if I understand it right, in audio CDs, it is the _length_ of the "on" area or "off" area along the track, rather than its mere presence (as in the data bit on a digital CD-ROM), that is important, sort of like the zero crossing distance, rather than the amplitude, is the real signal in an FM radio signal, and it is this ability to ignore signal amplitude that lends the audio CD its enhanced sound reproduction ability. As a result, there is a profound incompatibility between the data storage signal recovery methods for audio CDs versus digital CD-ROMS, even though the mechanics of reading with a laser and so on are very similar. If this is right, you can't use a CD player to read digital CD-ROMS without a whole separate signal extraction "mechanism" behind the read laser. If I'm all wet here, I'm sure someone in the group can correct/expand on this. None of this says you couldn't let the Amiga work to control the CD player as a CD player, which might be a fun project in itself. Kent, the man from xanth. <xanthian@Zorch.SF-Bay.ORG> <xanthian@well.sf.ca.us>
lphillips@lpami.wimsey.bc.ca (Larry Phillips) (12/03/90)
In <1990Dec2.073639.22387@zorch.SF-Bay.ORG>, xanthian@zorch.SF-Bay.ORG (Kent Paul Dolan) writes: >In article <90335.112615AXN100@psuvm.psu.edu> AXN100@psuvm.psu.edu writes: > >> I have a Pioneer (sp) 6pack player. On the back there are two pin-outs >> for a receiver to take control of the player. I was wondering if there >> was anyway for me to use these pin-outs to let my amiga take control >> of the CD player; thereby, making it into a CD-ROM jukebox. > >I'm no world class expert on CD-ROM, so take this with a grain of salt. > >Both digital CD-ROM and audio CDs use binary data on the media, in the >sense that it is either on or off, with no intermediate states. > >However, if I understand it right, in audio CDs, it is the _length_ of >the "on" area or "off" area along the track, rather than its mere >presence (as in the data bit on a digital CD-ROM), that is important, >sort of like the zero crossing distance, rather than the amplitude, is >the real signal in an FM radio signal, and it is this ability to ignore >signal amplitude that lends the audio CD its enhanced sound reproduction >ability. You are perhaps thinking of what happens somewhat after the data comes off the disk. PCM is the encoding technique used to translate between digital data and analog data, and NRZI encoding can be an intermediate stage, but what goes onto the CD is essentially the same in audio or CD-ROM, when looked at in terms of the way the individual bits are stored. In the case of CD-Audio, it is a code representing the instantaneous level of the sound recorded. In the case of CD-ROM, it is a code representing a byte value. >As a result, there is a profound incompatibility between the data >storage signal recovery methods for audio CDs versus digital CD-ROMS, >even though the mechanics of reading with a laser and so on are very >similar. There is an incompatibility, but it has more to do with the format of the data, rather than the way the bits are encoded. CD-ROM requires better error correction and a different 'block or sector' size and format. CD-Audio is in a format which is unsuitable for CD-ROM, but it is due to the lead-in, lead-out, sector sizes, etc. There is just too much overhead in the CD-Audio format to allow for good computer use. >If this is right, you can't use a CD player to read digital CD-ROMS >without a whole separate signal extraction "mechanism" behind the read >laser. This is probably correct, but mostly because the CD-Audio player interprets what it sees on the disk and treats it in the only way it knows how, which means that the data is treated as a continuous stream (one of only 99 streams (in music parlance, tracks, or bands) that may exist on the disk, another limitation of the CD-Audio format). Interestingly enough, many current production CD-ROM drives have the ability to recognize both the CD-ROM and CD-Audio formats, and can play sound from any part of the disk that is recorded appropriately. Yes, the two formats can exist on the same disk. DAT (Digital Audio Tape) is a similar thing, and a DAT drive intended for computer use can have audio capability as well (The Archive Python has a digital audio output jack on the back). >None of this says you couldn't let the Amiga work to control the CD >player as a CD player, which might be a fun project in itself. It would be. Sun's CD-ROM drives have audio capability, and a few of the fellows in our office have brought in headphones, and use a little OpenLook tool to play them. They seem to enjoy it. :-) I'm no expert either, but I do have a book called 'The Brady Guide to CD-ROM'. It's a fairly typical Brady book, but has more information content than most of them. -larry -- The only things to survive a nuclear war will be cockroaches and IBM PCs. +-----------------------------------------------------------------------+ | // Larry Phillips | | \X/ lphillips@lpami.wimsey.bc.ca -or- uunet!van-bc!lpami!lphillips | | COMPUSERVE: 76703,4322 -or- 76703.4322@compuserve.com | +-----------------------------------------------------------------------+
farren@well.sf.ca.us (Mike Farren) (12/03/90)
xanthian@zorch.SF-Bay.ORG (Kent Paul Dolan) writes: >In article <90335.112615AXN100@psuvm.psu.edu> AXN100@psuvm.psu.edu writes: >However, if I understand it right, in audio CDs, it is the _length_ of >the "on" area or "off" area along the track, rather than its mere >presence (as in the data bit on a digital CD-ROM), that is important, >sort of like the zero crossing distance, rather than the amplitude, is >the real signal in an FM radio signal, and it is this ability to ignore >signal amplitude that lends the audio CD its enhanced sound reproduction >ability. >If this is right, you can't use a CD player to read digital CD-ROMS >without a whole separate signal extraction "mechanism" behind the read >laser. >If I'm all wet here, I'm sure someone in the group can correct/expand on >this. You're all wet, Kent :-) The fact is that the data is _encoded_ onto the CD by way of the length of the "on" or "off" areas, but that's not really all that much different from something like MFM encoding for a disk. It's one level down from anything you need to concern yourself with - both CD audio and CDROM do this, and both give you pure digital data once you strip off the encoding. The format for the data that comes out, however, IS significantly different between the two different media, though, so you might have some problems there. CD's sound reproduction ability is simply due to their 16-bit A/D circuitry, leading to a 96db dynamic range, far superior to ANY analog recording mechanism. -- Mike Farren farren@well.sf.ca.us
brindley@ECE.ORST.EDU (Mike Brindley) (12/04/90)
A good, very readable, reference on compact discs is "The Compact Disc: A Handbook of Theory and Use," by Ken Pohlmann, 1989, A-R Editions. In this book, the author explains that CD-ROM data is placed on the CD in exactly the same way. The data is just treated differently once it has been decoded. Mike Brindley brindley@ece.orst.edu
lphillips@lpami.wimsey.bc.ca (Larry Phillips) (12/05/90)
In <842@pdxgate.UUCP>, jayward@eecs.cs.pdx.edu (Jay Ward) writes: >In article <2313@lpami.wimsey.bc.ca> lphillips@lpami.wimsey.bc.ca (Larry Phillips) writes: >>In <1990Dec2.073639.22387@zorch.SF-Bay.ORG>, xanthian@zorch.SF-Bay.ORG (Kent Paul Dolan) writes: >>>In article <90335.112615AXN100@psuvm.psu.edu> AXN100@psuvm.psu.edu writes: >>> >>>> I have a Pioneer (sp) 6pack player. On the back there are two pin-outs >>>> for a receiver to take control of the player. I was wondering if there >>>> was anyway for me to use these pin-outs to let my amiga take control >>>> of the CD player; thereby, making it into a CD-ROM jukebox. ^^^^^^^^^^^^^^^ >>> >>>I'm no world class expert on CD-ROM, so take this with a grain of salt. >>> >>>Both digital CD-ROM and audio CDs use binary data on the media, in the >>>sense that it is either on or off, with no intermediate states. >>> > >[MUCH STUFF ON THE OPERATION OF CD-ROM DELETED] > >I think that all the original poster wanted to do was to take control of >his CD player using his Amiga, not to use it as a CD-ROM player. You know, >control the six-pack using a nice Intuition Screen. > >Boy, give you techies an inch..... > >:-) >Message-ID: <49144@eerie.acsu.Buffalo.EDU> Heh heh... well, though 'jukebox' can be taken to be usical, it is also used for anything that can auto-change media for you. It was the reference to CD-ROM that made difference, since CD-ROM is very specifically NOT an audio format. -larry -- The only things to survive a nuclear war will be cockroaches and IBM PCs. +-----------------------------------------------------------------------+ | // Larry Phillips | | \X/ lphillips@lpami.wimsey.bc.ca -or- uunet!van-bc!lpami!lphillips | | COMPUSERVE: 76703,4322 -or- 76703.4322@compuserve.com | +-----------------------------------------------------------------------+
jayward@eecs.cs.pdx.edu (Jay Ward) (12/05/90)
In article <2313@lpami.wimsey.bc.ca> lphillips@lpami.wimsey.bc.ca (Larry Phillips) writes: >In <1990Dec2.073639.22387@zorch.SF-Bay.ORG>, xanthian@zorch.SF-Bay.ORG (Kent Paul Dolan) writes: >>In article <90335.112615AXN100@psuvm.psu.edu> AXN100@psuvm.psu.edu writes: >> >>> I have a Pioneer (sp) 6pack player. On the back there are two pin-outs >>> for a receiver to take control of the player. I was wondering if there >>> was anyway for me to use these pin-outs to let my amiga take control >>> of the CD player; thereby, making it into a CD-ROM jukebox. >> >>I'm no world class expert on CD-ROM, so take this with a grain of salt. >> >>Both digital CD-ROM and audio CDs use binary data on the media, in the >>sense that it is either on or off, with no intermediate states. >> [MUCH STUFF ON THE OPERATION OF CD-ROM DELETED] I think that all the original poster wanted to do was to take control of his CD player using his Amiga, not to use it as a CD-ROM player. You know, control the six-pack using a nice Intuition Screen. Boy, give you techies an inch..... :-) ---------------------------------------------------------------------------- Jay Ward --> jayward@eecs.cs.pdx.edu | if TrailBlazers > Opponents then | TrailBlazerWins++ ----------------------------------------------------------------------------
telam@pyrps5.pyramid.com (Thomas Elam) (12/06/90)
In article <90335.112615AXN100@psuvm.psu.edu>, AXN100@psuvm.psu.edu writes: |> |> I have a Pioneer (sp) 6pack player. On the back there are two |> pin-outs for a receiver to take control of the player. I was wondering |> if there was anyway for me to use these pin-outs to let my amiga take |> control of the CD player; thereby, making it into a CD-ROM jukebox. Could you please post the pin-outs or wiring diagrams? Thanks. |> Just Radom thoughts |> Ajai Tom
telam@pyrps5.pyramid.com (Thomas Elam) (12/06/90)
In article <1990Dec2.073639.22387@zorch.SF-Bay.ORG>, xanthian@zorch.SF-Bay.ORG (Kent Paul Dolan) writes: |> In article <90335.112615AXN100@psuvm.psu.edu> AXN100@psuvm.psu.edu writes: |> |> > I have a Pioneer (sp) 6pack player. On the back there are two pin-outs |> > for a receiver to take control of the player. I was wondering if there |> > was anyway for me to use these pin-outs to let my amiga take control |> > of the CD player; thereby, making it into a CD-ROM jukebox. |> |> I'm no world class expert on CD-ROM, so take this with a grain of salt. |> |> Both digital CD-ROM and audio CDs use binary data on the media, in the |> sense that it is either on or off, with no intermediate states. I agree. |> However, if I understand it right, in audio CDs, it is the _length_ of |> the "on" area or "off" area along the track, rather than its mere |> presence (as in the data bit on a digital CD-ROM), that is important, |> sort of like the zero crossing distance, rather than the amplitude, is |> the real signal in an FM radio signal, and it is this ability to ignore |> signal amplitude that lends the audio CD its enhanced sound reproduction |> ability. That would not be digital modulation. Digital modulation varies some aspect of the medium (for example, its optical diffusion or its local magnetic field) to precisely represent _numbers_ (often binary). What you are describing is Pulse Width Modulation (PWM). In PWM, the width of the pulses usually can meaningfully assume any value in a continuous range. Hence, PWM is _analog_. My explanation is not great, but I'm pretty sure of the essential idea. Audio CD's are digitally recorded on the medium. There are many recording errors, but these are corrected by big CRC's. I'm not sure, but I think audio CD's are recorded somewhat similarly to video CD's, because there are players that play both. On the other hand, could it be that the "pick up" is the same, but that the demodulation is different? Specifically, I'm wondering if the 4 or 5 MHz bandwidth needed for NTSC TV is obtained from a video disc by some kind of analog recording (perhaps the kind you described). |> As a result, there is a profound incompatibility between the data |> storage signal recovery methods for audio CDs versus digital CD-ROMS, |> even though the mechanics of reading with a laser and so on are very |> similar. I don't know. I do know that much of the technology from the audio CD's was adopted for CD-ROM's, allowing the large-scale economies of audio CD player manufacturing to reduce the costs of the CD-ROM players. |> If this is right, you can't use a CD player to read digital CD-ROMS |> without a whole separate signal extraction "mechanism" behind the read |> laser. |> |> If I'm all wet here, I'm sure someone in the group can correct/expand on |> this. |> |> None of this says you couldn't let the Amiga work to control the CD |> player as a CD player, which might be a fun project in itself. |> |> Kent, the man from xanth. |> <xanthian@Zorch.SF-Bay.ORG> <xanthian@well.sf.ca.us> Tom