Writing to a CD-RW using USB 1.1 is possible at 8x and 12x

I have an external CD-writer that I connected to my laptop using the
USB 1.1connection.
I tried writing at 8x speed using a CD-RW disk and was successful.
I also tried writing at 12x using a CD-RW disk and was successful
I tried writing using a CD-R disk at 8x and was not successful.
The data written on the disk was checked and there were no errors..

You do need the buffer underrun protection as the write buffer was
emptying and fulling at all the time during the writing.

The drive as a Cyber Combo drive that I put intop a case to make it
external.

Regards Brian

Brian wrote:
I have an external CD-writer that I connected to my laptop using the
USB 1.1connection.
I tried writing at 8x speed using a CD-RW disk and was successful.
I also tried writing at 12x using a CD-RW disk and was successful
I tried writing using a CD-R disk at 8x and was not successful.
The data written on the disk was checked and there were no errors..

You do need the buffer underrun protection as the write buffer was
emptying and fulling at all the time during the writing.

The drive as a Cyber Combo drive that I put intop a case to make it
external.

Sure, it's possible - with buffer underrun protection. If you time the
operation, you'll find that you can write more quickly if you use a
lower speed - the time needed each time protection kicks in is substantial.

Of course, you want to stay within the bounds of your blank, which is
one reason you shouldn't put an UltraSpeed drive on USB 1.1.

Mike
--

http://www.mrichter.com/

There is no way that you can write at 8 or 12 times via a USB1.1 connection.
4x is the maximum that the interface will allow, on a good day with the wind
behind it. The writer may actually write the chunks of data faster but it
will be making constant use of Buffer Underrun protection and/or spinning
the disc up and down. The chances of making an error free disc like this are
much reduced, and the only justification for doing so is an unavailability
of low speed media.

USB2 on the other hand has no such limitation.

--

Graham Mayor



Brian wrote:
I have an external CD-writer that I connected to my laptop using the
USB 1.1connection.
I tried writing at 8x speed using a CD-RW disk and was successful.
I also tried writing at 12x using a CD-RW disk and was successful
I tried writing using a CD-R disk at 8x and was not successful.
The data written on the disk was checked and there were no errors..

You do need the buffer underrun protection as the write buffer was
emptying and fulling at all the time during the writing.

The drive as a Cyber Combo drive that I put intop a case to make it
external.

Regards Brian

Hi Graham,
I've proved it can be done by writing to a
CD-RW disc rated at 1-10x using 8x writing speed then I formatted the
disk and wrote at 12x speed. I put over 500 megs of files on the CD-RW
and all read back ok.
However I was not able to write to a 8x CD-R.

It may depend on the brand of the CD writer as to the success of
writing using a USB 1.1 connection.

My Laptop has a USB 1.1 and being a laptop there's no way of upgrading
to a USB 2.0 device, so I'm thankfull that I can write to a CD-RW
disk.

Regards Brian



"Graham Mayor" wrote:

There is no way that you can write at 8 or 12 times via a USB1.1 connection.
4x is the maximum that the interface will allow, on a good day with the wind
behind it. The writer may actually write the chunks of data faster but it
will be making constant use of Buffer Underrun protection and/or spinning
the disc up and down. The chances of making an error free disc like this are
much reduced, and the only justification for doing so is an unavailability
of low speed media.

USB2 on the other hand has no such limitation.

USB1.1 is not capable of providing a continuous data stream faster than that
required for 4X. If you are writing faster, then the writer will be
constantly stopping and starting and making use of burnproof technology,
which is not ideal.

If your laptop has a PCMCIA port then you can upgrade to USB2 - Adaptec
offers a suitable adapter, as do one or two other manufacturers.

--

Graham Mayor



Brian wrote:
Hi Graham,
I've proved it can be done by writing to a
CD-RW disc rated at 1-10x using 8x writing speed then I formatted the
disk and wrote at 12x speed. I put over 500 megs of files on the CD-RW
and all read back ok.
However I was not able to write to a 8x CD-R.

It may depend on the brand of the CD writer as to the success of
writing using a USB 1.1 connection.

My Laptop has a USB 1.1 and being a laptop there's no way of upgrading
to a USB 2.0 device, so I'm thankfull that I can write to a CD-RW
disk.

Regards Brian



"Graham Mayor" wrote:

There is no way that you can write at 8 or 12 times via a USB1.1
connection. 4x is the maximum that the interface will allow, on a
good day with the wind behind it. The writer may actually write the
chunks of data faster but it will be making constant use of Buffer
Underrun protection and/or spinning the disc up and down. The
chances of making an error free disc like this are much reduced, and
the only justification for doing so is an unavailability of low
speed media.

USB2 on the other hand has no such limitation.

"Graham Mayor" wrote
There is no way that you can write at 8 or 12 times via a USB1.1
connection.
4x is the maximum that the interface will allow, on a good day with the
wind
behind it. The writer may actually write the chunks of data faster but it
will be making constant use of Buffer Underrun protection and/or spinning
the disc up and down. The chances of making an error free disc like this
are
much reduced, and the only justification for doing so is an unavailability
of low speed media.

USB2 on the other hand has no such limitation.

The wind obviously blows more strongly and reliably in the southern
hemisphere. If I remember correctly USB 1.1 devices can aggregate data
channels for a maximum throughput of 8 Mbits per second, which translates to
6.67X. I briefly had a 52X LiteOn connected to a portable's 1.1 port.
Whether set to 52X or 8X the burner rapidly slowed to 6.2-6.5X (Nero
registry hack to enable display of write speed). No buffer underruns
although the recorder's buffer was fluctuating wildly between 10 and 80%.
Overall speed including leadin and out worked out a shade under 6X. So you
can under some circumstances do better than 4X, but certainly not 8X.

I'll happily swap some of your wind for some of our rain
The fact remains that the interface is the limiting factor and 8 or 12 X are
not true write speeds.

--

Graham Mayor




ned ludd wrote:
"Graham Mayor" wrote
There is no way that you can write at 8 or 12 times via a USB1.1
connection. 4x is the maximum that the interface will allow, on a
good day with the wind behind it. The writer may actually write the
chunks of data faster but it will be making constant use of Buffer
Underrun protection and/or spinning the disc up and down. The
chances of making an error free disc like this are much reduced, and
the only justification for doing so is an unavailability of low
speed media.

USB2 on the other hand has no such limitation.

The wind obviously blows more strongly and reliably in the southern
hemisphere. If I remember correctly USB 1.1 devices can aggregate
data channels for a maximum throughput of 8 Mbits per second, which
translates to
6.67X. I briefly had a 52X LiteOn connected to a portable's 1.1 port.
Whether set to 52X or 8X the burner rapidly slowed to 6.2-6.5X (Nero
registry hack to enable display of write speed). No buffer underruns
although the recorder's buffer was fluctuating wildly between 10 and
80%. Overall speed including leadin and out worked out a shade under
6X. So you can under some circumstances do better than 4X, but
certainly not 8X.

The drive can't write slower than 8x speed
At both 8x and 12x the data buffer is constantly fulling up and
writing to the drive in short bursts.
It takes longer for the drive to write a CD-R but at least it does
work.
It looks like manufactors are not supporting slower CD-R/RW media.
The same could happen to DVD writers as at the moment most can write
at 2x speed.

Regards Brian


"ned ludd" wrote:


"Graham Mayor" wrote
There is no way that you can write at 8 or 12 times via a USB1.1
connection.
4x is the maximum that the interface will allow, on a good day with the
wind
behind it. The writer may actually write the chunks of data faster but it
will be making constant use of Buffer Underrun protection and/or spinning
the disc up and down. The chances of making an error free disc like this
are
much reduced, and the only justification for doing so is an unavailability
of low speed media.

USB2 on the other hand has no such limitation.

The wind obviously blows more strongly and reliably in the southern
hemisphere. If I remember correctly USB 1.1 devices can aggregate data
channels for a maximum throughput of 8 Mbits per second, which translates to
6.67X. I briefly had a 52X LiteOn connected to a portable's 1.1 port.
Whether set to 52X or 8X the burner rapidly slowed to 6.2-6.5X (Nero
registry hack to enable display of write speed). No buffer underruns
although the recorder's buffer was fluctuating wildly between 10 and 80%.
Overall speed including leadin and out worked out a shade under 6X. So you
can under some circumstances do better than 4X, but certainly not 8X.