Re: MD: MO technology and MD data usage
>[EMAIL PROTECTED] wrote: > > Due to a high error ratio of a minidisc (which isn't a problem for audio) > > it is not as suitable for data as you'd think, which leads to a lot of > > redundancy, ie the disk will probably be much less than 140 Mb, more like > > 100-120 > >Huh??? > >1) MD-Data == 140MB. you're right, got that correction from another member already, always thought that the disk was 140 Mb's raw, turns out to be about 160, my mistake. >2) MD-Data uses another error correction algorithm than MD-Audio Of course, if you'd use the audio correction you'd have a lot more errors >3) MD-Data uses another type of disk >4) MD-Data != MD-Audio I know, I know >MD-Data was an attempt of Sony to introduce a portable media based on >MO technology. It had three major problems: > >1) To expensive: >Drives costed about $1000,- at the introduction. >2) SCSI 2 >MD-Data drives connected to SCSI-2. Back in 1994? (Rick, help me out), >during the introduction of MD-Data, SCSI-2 interfaces where expensive. >Almost at the same time, the ZIP drive was introduced. The media was >almost the same price, but the drive was about 3 times less expensive! >And it connected to the Parallel port! >3) To slow >150kBs was to slow compared to other portable media back then. You could >buy a 240MB 3.5" MO drive for a 'few' dollars more, that outperformed the >MD-Data drive. Yep, indeed, I know the problem, right now, buy a SCSI 2 Gb Jazz, thos things are cool... >Cheers, >Ralph -> Who is glad that there are other Dutch on this list. Greetingz, en 'tga je goed. Guess, you know C, Java or javascript... (the == and !=)... Bye, Remko van der Vossen, [EMAIL PROTECTED] The Black Angel, [EMAIL PROTECTED] ICQ: 48056779 EDA and owner of [EMAIL PROTECTED] fan of Jewel, The X-Files, Chris Carter, Mac Gyver, BtVS, Jane Jensen's Gabriel Knight Pretty; "There is a pretty girl on the Face of this magazine And all I can see are my dirty hands turning the page" Jewel - To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
Re: MD: MO technology and MD data usage
[EMAIL PROTECTED] wrote: > Due to a high error ratio of a minidisc (which isn't a problem for audio) > it is not as suitable for data as you'd think, which leads to a lot of > redundancy, ie the disk will probably be much less than 140 Mb, more like > 100-120 Huh??? 1) MD-Data == 140MB. 2) MD-Data uses another error correction algorithm than MD-Audio 3) MD-Data uses another type of disk 4) MD-Data != MD-Audio MD-Data was an attempt of Sony to introduce a portable media based on MO technology. It had three major problems: 1) To expensive: Drives costed about $1000,- at the introduction. 2) SCSI 2 MD-Data drives connected to SCSI-2. Back in 1994? (Rick, help me out), during the introduction of MD-Data, SCSI-2 interfaces where expensive. Almost at the same time, the ZIP drive was introduced. The media was almost the same price, but the drive was about 3 times less expensive! And it connected to the Parallel port! 3) To slow 150kBs was to slow compared to other portable media back then. You could buy a 240MB 3.5" MO drive for a 'few' dollars more, that outperformed the MD-Data drive. Cheers, Ralph -> Who is glad that there are other Dutch on this list. -- === Ralph SmeetsFunctional Verification Centre Of Competence - CMG Voice: (+33) (0)4 76 58 44 46 STMicroelectronics Fax:(+33) (0)4 76 58 40 11 5, chem de la Dhuy Mobile: (+33) (0)6 82 66 62 70 38240 MEYLAN E-Mail: [EMAIL PROTECTED] FRANCE === "For many years, mankind lived just like the animals. And then something happened that unleashed the powers of our imagination: We learned to talk." -- Stephen Hawking, later used by Pink Floyd -- === - To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
Re: MD: MO technology and MD data usage
[EMAIL PROTECTED] wrote: > > I would question your first point... ;) > > Agree that write speed would be less than read speed; however if you > consider that a MD recorder can accept a streaming digital input of CD > quality audio (via the optical in), encode it with ATRAC, AND write it to > the disk, all in real-time - then i think you'll find the bandwidth of the > system quite sufficient for removable media purposes on a PC. Plus the > benefit of the disks not being as easily affected (as floppies) by magnetic > fieldsit all adds up... > > In any case it would be vastly better than floppy drive technology which > should have been obseleted years ago... > > IMO anyways ;) An MD is read/written at 150kBs Do you remember those first CD-ROM drives? Cheers, Ralph -> 40x MD-Data with IDE interface would be a breakthrough. 1x MD-Data using SCSI 2 is like returning to the dark ages -- === Ralph SmeetsFunctional Verification Centre Of Competence - CMG Voice: (+33) (0)4 76 58 44 46 STMicroelectronics Fax:(+33) (0)4 76 58 40 11 5, chem de la Dhuy Mobile: (+33) (0)6 82 66 62 70 38240 MEYLAN E-Mail: [EMAIL PROTECTED] FRANCE === "For many years, mankind lived just like the animals. And then something happened that unleashed the powers of our imagination: We learned to talk." -- Stephen Hawking, later used by Pink Floyd -- === - To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
RE: MD: MO technology and MD data usage
From: Magic > I think I would rather boot my OS from something > that looked like a brick than a "Hello Kitty" > anything! Damned straight. I got a semi-random selection of blanks mailed to me from a friend living in Japan for a few years. I was certain that they'd send a 'Hello-Kitty' disc in there just to bug me. Thankfully they didn't, but the pink Sony Lumina disc is bad enough... Rick. -+--- [EMAIL PROTECTED] http://www.alienshore.com/ - To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
Re: MD: MO technology and MD data usage
From: Hannes Rohde <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Saturday, November 27, 1999 1:33 PM Subject: Re: MD: MO technology and MD data usage Hannes made the comment: > After all, minidiscs look far better than zip discs! I agree Hannes then trashed his own statement by saying: > (Imagine booting your favourite OS from a "Hello Kitty" disc!) Sorry, your argument was that MDs look better than ZIP? I think I would rather boot my OS from something that looked like a brick than a "Hello Kitty" anything! Magic -- "Creativity is more a birthright than an acquisition, and the power of sound is wisdom and understanding applied to the power of vibration." Location : Portsmouth, England, UK Homepage : http://www.mattnet.freeserve.co.uk EMail : [EMAIL PROTECTED] - To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
Re: MD: MO technology and MD data usage
Remko van der Vossen wrote: > >if you consider that a MD recorder can accept a streaming > >digital input of CD quality audio (via the optical in), encode > >it with ATRAC, AND write it to the disk, all in real-time - > >then i think you'll find the bandwidth of the system quite > >sufficient for removable media purposes on a PC. > Mind you that 44.1 KHz stereo 16 bits is only 176 Kb/s and that > ain't much at all, That's the speed of a 1x cdrom drive... Anyone remember those things? Compared to todays standards, it's awfully slow... (The 44100*2*2 calculation is not 100% correct for minidiscs: ATRAC compresses the audio data to 1/5 of the ammount, so transfer speed could be reduced to 1/5 of 176kB/s, but the minidisc units still read/write at full speed, and read/write operations only take 1/5 of the time; the unit is idle 4/5 of the time) > granted a normal floppy drive is slower, but a decent Zip drive > can easily manage 600 Kb/s ... which is one reason for zip's success and MD/Data's failure. Despite all drawbacks, I would still like to see a decent MD/Data drive: takes audio MDs, allows for 120-140 MB of data, will record mp3s/wave files, let's me title discs via keyboard... After all, minidiscs look far better than zip discs! (Imagine booting your favourite OS from a "Hello Kitty" disc!) Bye, Hannes - To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
RE: MD: MO technology and MD data usage
At 07:33 PM 11/26/99 -0500, you wrote: >I would question your first point... ;) > >Agree that write speed would be less than read speed; however if you >consider that a MD recorder can accept a streaming digital input of CD >quality audio (via the optical in), encode it with ATRAC, AND write it to >the disk, all in real-time - then i think you'll find the bandwidth of the >system quite sufficient for removable media purposes on a PC. Plus the >benefit of the disks not being as easily affected (as floppies) by magnetic >fieldsit all adds up... Mind you that 44.1 KHz stereo 16 bits is only 176 Kb/s and that ain't much at all, granted a normal floppy drive is slower, but a decent Zip drive can easily manage 600 Kb/s >In any case it would be vastly better than floppy drive technology which >should have been obseleted years ago... Due to a high error ratio of a minidisc (which isn't a problem for audio) it is not as suitable for data as you'd think, which leads to a lot of redundancy, ie the disk will probably be much less than 140 Mb, more like 100-120 Bye, Remko van der Vossen, [EMAIL PROTECTED] The Black Angel, [EMAIL PROTECTED] ICQ: 48056779 EDA and owner of [EMAIL PROTECTED] fan of Jewel, The X-Files, Chris Carter, Mac Gyver, BtVS, Jane Jensen's Gabriel Knight Pretty; "There is a pretty girl on the Face of this magazine And all I can see are my dirty hands turning the page" Jewel - To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
RE: MD: MO technology and MD data usage
I would question your first point... ;) Agree that write speed would be less than read speed; however if you consider that a MD recorder can accept a streaming digital input of CD quality audio (via the optical in), encode it with ATRAC, AND write it to the disk, all in real-time - then i think you'll find the bandwidth of the system quite sufficient for removable media purposes on a PC. Plus the benefit of the disks not being as easily affected (as floppies) by magnetic fieldsit all adds up... In any case it would be vastly better than floppy drive technology which should have been obseleted years ago... IMO anyways ;) L8r, mark... -Original Message- Subject: Re: MD: MO technology and MD data usage The write speed is probably the biggest problem (ie I would think the read speed would be less of a factor) - there is a finite time taken to heat the metallic substrate to it's Curie Point and also a finite time from that point for the write magnetic head to align the substrate. The factors governing the time taken for these events are probably related to laser power output and disc groove/spot size. The groove and spot size is fixed by the MD format and laser power output is probably limited by cost and physical size in relation to fitting it in a portable recorder. - To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
Re: MD: MO technology and MD data usage
I think there are a couple of reasons for this: The write speed is probably the biggest problem (ie I would think the read speed would be less of a factor) - there is a finite time taken to heat the metallic substrate to it's Curie Point and also a finite time from that point for the write magnetic head to align the substrate. The factors governing the time taken for these events are probably related to laser power output and disc groove/spot size. The groove and spot size is fixed by the MD format and laser power output is probably limited by cost and physical size in relation to fitting it in a portable recorder. Computer MO technology may not be as limited by physical disc size or laser power. Maybe the playback (read) rate could be increased to acceptable levels by increasing the speed of the disc when reading, as in computer CD-ROM readers, but I don't think it would be as easy to do this when writing to disc ATRAC would not be used in Data drives - it is a 'lossy' system and would not be suitable. It's my opinion that ATRAC is required by the MD (audio) format to reduce the amount of data to acceptable levels that the format can cope with when writing ie I doubt that the small size of disc and relatively low power of the MD laser could cope with raw CD size data of 16 bit x 44.1 Khz Further to that, it's possible that the small size of MD came about as a 'by product' of the fact that maybe it was (in 1990, when MD was in development) impossible to write to MO discs at a suitable (raw CD) rate in real time, hence ATRAC reduced the data rate to acceptable levels but then Sony found that they only needed a small disc to hold the data All the above is just IMHO. GB >What's the difference between MD and computer Magneto-Optical technology >that makes MiniDisc unsuitable for data use? Is it to do with Atrac, or >what? - To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
MD: MO technology and MD data usage
Hey everybody I've followed a number of threads on the list about using MDs (or not) for data storage. The consensus seems to be that the access and transfer rates are too slow to be useful. What I can't work out is why this is. I have a Fujitsu 3.5" 230MB magneto optical drive, which (I believe) uses the same kind of MO storage as MD. Even on a wobbly old ISA SCSI card, it gives very acceptable performance. What's the difference between MD and computer Magneto-Optical technology that makes MiniDisc unsuitable for data use? Is it to do with Atrac, or what? Like most MD people, I'd love to use the handy wee discs in preference to scappy Zip discs. My 230MB MO drive is great - the discs are cheap (£5) and seem virtually indestructable. Why isn't there more MO technology in use? Cheers Alan - To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
