Unknown Disc Usage

Electronics Computer Programming Q&A
Robert Reed
Posts: 2276
Joined: Wed Nov 24, 2004 1:01 am
Location: ASHTABULA,OHIO
Contact:

Unknown Disc Usage

Post by Robert Reed » Sat Sep 12, 2009 8:15 pm

I have just received a pack of Taiyo Yuden CDs. They have a pure white back on them with no markings. A tag near the bottom of the pile says:
US 52X CD-R

Anybody know what they are good for and what all I can do with them? ( read,write, whatever)

User avatar
MrAl
Posts: 3862
Joined: Fri Jan 11, 2002 1:01 am
Location: NewJersey
Contact:

Re: Unknown Disc Usage

Post by MrAl » Sat Sep 12, 2009 10:56 pm

Hi Robert,


Since they read "CD-R" wouldnt that mean that they are recording CD's ?
CD-R means they can be recorded but not erased. CD-RW means they
can be both recorded and erased a limited number of times.
"52x" would mean the speed is 52x, which means they are modern CDs.

That name make is supposed to be decent btw.
LEDs vs Bulbs, LEDs are winning.

User avatar
sofaspud
Posts: 531
Joined: Wed Feb 13, 2002 1:01 am
Location: San Antonio, TX
Contact:

Re: Unknown Disc Usage

Post by sofaspud » Sun Sep 13, 2009 7:55 am

There is a small freeware program, CDR Identifier, that is able to read the disc and
report stuff like manufacturer, type, capacity, and speed.
Pretty handy when you have any of those "generic-labelled" discs.

User avatar
CeaSaR
Posts: 1688
Joined: Sat Nov 08, 2003 1:01 am
Location: Phoenixville, PA USA
Contact:

Re: Unknown Disc Usage

Post by CeaSaR » Sun Sep 13, 2009 9:34 am

CDR capacities I have seen are between 650 - 700 MB. I haven't seen the 650's in along time
so they most likely are 700's. Some may go up to 720, but I wouldn't count on it.

CeaSaR
Hey, what do I know?

Robert Reed
Posts: 2276
Joined: Wed Nov 24, 2004 1:01 am
Location: ASHTABULA,OHIO
Contact:

Re: Unknown Disc Usage

Post by Robert Reed » Tue Sep 15, 2009 1:31 pm

MrAl
So CD-R can be written one time and then it is permanent forever. Is that correct?
I don't do a lot of work with CDs, so I am not all that familiar with their terminology.
I see all kinds of labels (CD-R, CD-RW, CD+RW and on and on), but have never taken the time to explore these designators functions. What all is out there and what should I look for in what they can do? Also I have heard that TY discs are superior - although one would think that they would have at least taken the effort to label them as to their function.

SofaSpud
Where is that freeware?

User avatar
haklesup
Posts: 2933
Joined: Thu Aug 01, 2002 1:01 am
Location: San Jose CA
Contact:

Re: Unknown Disc Usage

Post by haklesup » Tue Sep 15, 2009 1:54 pm

So CD-R can be written one time and then it is permanent forever. Is that correct?
Thats correct and you can add that if you do not fill the disk, you can usually continue to add files (or delete them) until the capacity is reached so long as you do not close (or finalize) the disk. Finalizing the disc makes it act like a factory disk (no write any more). Often CD-R are called CDROM but technically that should apply to only factory pressed discs. I think its funny that R stands for Read but it would be pointless to make blank CDs you could only read.

CD-RW, CD+RW are just slightly different formats but the point is moot now since most drives can read or write either kind. If you have a particularly old drive, there might be compatibility issues with the wrong kind of disc. Just about any DVD-RW drive will be cross compatible with any kind of CD.
SofaSpud
Where is that freeware?
the link is embedded in the words "CD Identifier" in his post. We all wish the contrast for embedded link color was better than it is so it would be easier to see. Often it blends in with the rest of the text.

User avatar
CeaSaR
Posts: 1688
Joined: Sat Nov 08, 2003 1:01 am
Location: Phoenixville, PA USA
Contact:

Re: Unknown Disc Usage

Post by CeaSaR » Tue Sep 15, 2009 3:13 pm

Robert,

CD-R's (and the lesser known CD+R) are what is know as a WORM media: Write Once Read Many.
In this incarnation, the information is written once and the disc is then closed so that no more
information can be written to the disc, effectively telling the drive reading it that it is full. While
the connotation is that you may only record once, there is the option of writing Sessions.
What this does is keeps the disc from being closed so that more info can be written at a later date.
The caveat that goes along with it is that there is a 20 MB overhead each time you end a session,
that space is used to separate the data and give info on how much space was used, etc. I never
quite understood why they needed 20 MB for that, but they do.

Ultimately you may write info to the disc until it is full, but you lose space each time you do it in
"chunks", so it makes sense to wait until you have a goodly amount of files before writing them.
IE, you don't want to write just one 45kB file to a CD and end the session. That file will eat up
20045 kB +- so that if you do single files like that, the ~700 MB disc will be full even though the
actual size of the files could be less than 100 MB.

BTW, they say that the shelf life of written CD's is about 30 years. That is if they are kept in cases
and out of they sun and heat/cold.

CeaSaR
Hey, what do I know?

Robert Reed
Posts: 2276
Joined: Wed Nov 24, 2004 1:01 am
Location: ASHTABULA,OHIO
Contact:

Re: Unknown Disc Usage

Post by Robert Reed » Tue Sep 15, 2009 3:48 pm

Hacklesup & Ceasar
I'm seeing a slight discrepancy in your replys as to read/write.
If I understand so far:
The labeling does not make a whole lot of difference ,especially if I have a newer drive (mine is two years old).
I can actually write, erase (delete) and rewrite to these discs as long as I adhere to certain rules-
Do not completely fill disc ( 700 Mbyte in this case).
Do not press some MAGIC key to tell the disc it is full.
Pay a 20 Mbyte penalty every time I add segments of data to the disc, be that small or large.

If that is so, then I guess I can live with this product.

Thanks, Robert

User avatar
haklesup
Posts: 2933
Joined: Thu Aug 01, 2002 1:01 am
Location: San Jose CA
Contact:

Re: Unknown Disc Usage

Post by haklesup » Tue Sep 15, 2009 9:49 pm

Let me be a little clearer

On a CD-RW disk when you delete a file you actually recover the area on the disk so you can reuse it later for other files. On a CD-R disk, when you erase it's like crossing our words on a sheet of paper, you can't really write on those lines again, you have to move further down the paper and once the sheet is full, youre done with it.

CDs are great for long term data storage but not forever. I've read that the data can degrade but AFAIK, I have never lost data on a disk I wrote on. So I don't know how long but theyre pretty reliable for a few years at least. Fro transporting files though, you can't beat flash based memory like USB drives or SD cards etc. They're tiny compared to a CD and hold lots lots more data. Try fitting a disk in your pocket and see what your friends say.

OTOH, you can't beat the price of blank CD-R disks. If you want to give files to friends family or collegues, its the best media. CDR and CDRW disks are so cheap now, I don't bother with rewriting them anyway, its so much easier to grab a fresh one since they're cheaper than 1 minute of long distance calling from a landline (ATT regular rates )

I'm just happy AOL stopped sending me piles of them

User avatar
CeaSaR
Posts: 1688
Joined: Sat Nov 08, 2003 1:01 am
Location: Phoenixville, PA USA
Contact:

Re: Unknown Disc Usage

Post by CeaSaR » Tue Sep 15, 2009 9:57 pm

Robert,

Your drive is fine if it is only 2 years old and can use the CDR.

You can write, delete and continue to write data to the CDR. Delete does not remove
it from the disc, it only destroys that data's info in the File Allocation Table that tells the
drive where to find that data. You can never recover data space for re-use from a CDR.

You can get pretty darn close to completely filling a CDR, it all depends on what the real
size of the files are as compared to the cluster allocations needed to write to the CDR.
You may find that the combined size of the files may be less than what the computer says
they are.

The "magic key" is in the CD burner program. It will say "Finalize Disc". This will write both the
lead-in and the lead-out so that the disc shows no available space.

20 MB penalty is the price you pay for incremental use of the disc. We all pay that one. The
only way to get around that is to carefully plan your burn to place as much as possible in the
"Track Layout" (or whatever your destination window says) and burn it as "Disc-at-Once".
That will burn everything to the disc and close it. If done right, you can get just about the full
amount on the disc that the label says.

*CDR stands for Compact Disc Recordable. This is the type you have indicated.
*CDRW stands for Compact Disc Re-Writeable. You do not have this type.

The BIG difference between these is that the CDR can only be filled up (completely used) once.
The data initially written to the disc is always there even if you tell Explorer to delete it.

The CDRW can be used over and over again like your computer's hard disc drive. When you delete
data from the CDRW, that space becomes free again to be used over. There is a lifespan to the disc,
I think I read 1000 writes or so, but that was a long time ago and things are probably different now.

If you want any more clarification or tips on how to do a successful burn, just ask and I'll be
more than happy to share my experience.

CeaSaR
Hey, what do I know?

User avatar
CeaSaR
Posts: 1688
Joined: Sat Nov 08, 2003 1:01 am
Location: Phoenixville, PA USA
Contact:

Re: Unknown Disc Usage

Post by CeaSaR » Tue Sep 15, 2009 10:01 pm

Darn it Hacklesup! You keep beating me to the post. :razz:

That's okay, the more information delivered can only help clarify the answer(s).
As they say, 2 heads are better than 1! In this case, 3 heads...

CeaSaR
Hey, what do I know?

User avatar
MrAl
Posts: 3862
Joined: Fri Jan 11, 2002 1:01 am
Location: NewJersey
Contact:

Re: Unknown Disc Usage

Post by MrAl » Wed Sep 16, 2009 1:31 am

Robert Reed wrote:MrAl
So CD-R can be written one time and then it is permanent forever. Is that correct?
I don't do a lot of work with CDs, so I am not all that familiar with their terminology.
I see all kinds of labels (CD-R, CD-RW, CD+RW and on and on), but have never taken the time to explore these designators functions. What all is out there and what should I look for in what they can do? Also I have heard that TY discs are superior - although one would think that they would have at least taken the effort to label them as to their function.

SofaSpud
Where is that freeware?

Hi Robert,

Pretty much yes, the CD-R can only be written to once and that is it.
The only other thing with them is that you can write over files, and add stuff later, but
anything written over is not really erased it is just skipped, so the space on the disk
is not recovered. Thus, if you write a 100Megabyte file to the disk and then later
write that same file again, the original 100MB disappears and the new one takes its
place, but the total space used on the disk now is 200MB even though you cant see
the original 100MB file on the disk anymore. Thus if you are using a 700MB disk and
you did those two 100MB files you have only 500MB left on the disk while you can only
see and use one 100MB file, so 100MB is lost forever.

CD-RW and CD+RW
These are read write formats. The disk can be erased later, or with some burners (hardware)
the disk can simply be used like a hard disk. I can not recommend using these disks however
as they dont seem to be very reliable, and they certainly do not allow read and write as
many times as the advertising would lead you to believe. They quote something like 1000
rewrites, but it is more like 10 or 15. Since the capacity is low by todays standards anyway,
the best way to go for read write accessibility is to use a USB stick instead.
LEDs vs Bulbs, LEDs are winning.

Robert Reed
Posts: 2276
Joined: Wed Nov 24, 2004 1:01 am
Location: ASHTABULA,OHIO
Contact:

Re: Unknown Disc Usage

Post by Robert Reed » Wed Sep 16, 2009 3:56 pm

OK guys, thanks for bringing me up to speed on this subject. I guess for long life and critical data the TY CD-R is a good way to go inspite of some drawbacks. I did purchase a USB stick (I think it was called a flash drive) a while back so as to back up my 'C' drive. It is 16 Mbyte and cost me $20. Nice and compact but kind of pricey for everyday work.

User avatar
sofaspud
Posts: 531
Joined: Wed Feb 13, 2002 1:01 am
Location: San Antonio, TX
Contact:

Re: Unknown Disc Usage

Post by sofaspud » Wed Sep 16, 2009 6:32 pm

Something I didn't see mentioned...
Robert, I take it you are concerned with burning backup files to a blank disc. Virtually all CDR-burner software has
the option of creating data or music CDs, so be sure you select the right type.
I've burned 100s and 100s of blank discs, both data and music. I feel CDRW are obsolete - flash devices are far
superior in every respect (that should be 16Gbyte not Mbyte shouldn't it?). I have never "deleted" files from a CDR.
What's the point when I can't reclaim the space? I also never leave a session open, but my understanding is that
a disc whose session is left open cannot be read from until it is closed. Again, what's the point? I prefer to gather a
full disc's worth of backups and burn all the files at one time. Then I use the ol' DOS print redirect command* to make
a text file of the contents. YMMV, but I thought these techniques might be helpful.

*umm, goes something like: dir m:\*.* /s > c:\work\bkupcd01.txt Don't quote me on that, though. I do that on my
Win98 box; my brain works different on this Vista machine.

User avatar
Janitor Tzap
Posts: 1416
Joined: Sat Aug 12, 2006 5:17 pm
Contact:

Re: Unknown Disc Usage

Post by Janitor Tzap » Thu Sep 17, 2009 7:46 am

sofaspud wrote:Something I didn't see mentioned...
Robert, I take it you are concerned with burning backup files to a blank disc. Virtually all CDR-burner software has
the option of creating data or music CDs, so be sure you select the right type.
I've burned 100s and 100s of blank discs, both data and music. I feel CDRW are obsolete - flash devices are far
superior in every respect (that should be 16Gbyte not Mbyte shouldn't it?). I have never "deleted" files from a CDR.
What's the point when I can't reclaim the space? I also never leave a session open, but my understanding is that
a disc whose session is left open cannot be read from until it is closed. Again, what's the point? I prefer to gather a
full disc's worth of backups and burn all the files at one time. Then I use the ol' DOS print redirect command* to make
a text file of the contents. YMMV, but I thought these techniques might be helpful.

*umm, goes something like: dir m:\*.* /s > c:\work\bkupcd01.txt Don't quote me on that, though. I do that on my
Win98 box; my brain works different on this Vista machine.
I've been able to look at open session DVD's.
But only on the Burner that wrote the session to that disc.
I've done this many times, when I am grouping together 10 or 20 minute video clips, on to one DVD disc.
Then I will finalize the disc so it can be used on any other players.

As for CD-R's.....
Yeah, I normally just keep adding data to a disk till it becomes full.
And I normally use the CD-R's for driver updates for: Video Cards, Audio, BIOs, Main Board, and other Devices that I have.


Signed: Janitor Tzap

Post Reply

Who is online

Users browsing this forum: No registered users and 9 guests