buffer underrun???
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Thread: buffer underrun???

  1. #1

    buffer underrun???

    greetings...

    There are seven CDs of ClipArt and i have to copy it to one blank DVD. I am using "Toast" of Mac TigerX OS. But there is an error occured.... what's this??? Please help

    The drive reported an error:
    Sense Key = ILLEGAL REQUEST
    Sense Code = 0x21, 0x02
    BUFFER UNDERRUN

  2. #2
    Banned
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    Well, the Wiki is open for discussion but if you look at http://en.wikipedia.org/wiki/Buffer_underrun you might find the answer.

    Basically, there's a buffer and from one side something is writing to it and the other side is reading from it. Think about the buffer as a sink, with a running tap filling it while the drain pipe is draining the water away again. Imagine that someone is continuously toying around with the tap, making it run faster or slower all the time.
    In an overrun situation, the tap is adding water faster to the sink than the drain can drain it. Thus the sink will fill until it can't hold any water anymore and then it starts to flood.
    In an underrun situation, the tap is adding water slower than the drain can drain it. So basically, the drain is already draining the water before it can collect in the sink. Now, this normally would not be a problem but if this sink is supposed to deliver a constant stream of water to some other place, then this will get interrupted because at some point, it has nothing that can be drained. The sink is there so the drain will have a constant amount to feed to whatever needs to be fed. But if the sink is empty and the user closed the tap to just some drips of water, the drain will fail to provide a constant stream of water and thus causing a problem somewhere else.
    The tap must be turned to let more water flow in the sink to fix this, the sink must be bigger so it can store more water or the drain must be adjusted to drain the sink at a slower speed. In the latter case, you have a problem with the overrun again if the person then desides to turn the tap wide open again. Hopes this visualisation makes error clear. Solution? Maybe reduce the speed at which you are burning these CD's... (Making the drain pipe smaller)

  3. #3
    Senior Member
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    As Katja said reducing the burning speed ususally helps also a lot of burning software has an option to turn on Buffer Underrun Protection which allows the software to manage the speed.
    \"You got a mouth like an outboard motor..all the time putt putt putt\" - Foghorn Leghorn

  4. #4
    thanks for the great explanation... you're really good...

    P.S.
    Is that you posted on your Avatar? You're pretty...

  5. #5
    Senior Member
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    P.S.
    Is that you posted on your Avatar? You're pretty...
    No actually it's Foghorn Leghorn. Oh you meant Katja
    \"You got a mouth like an outboard motor..all the time putt putt putt\" - Foghorn Leghorn

  6. #6
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    Originally posted here by Jeckgo
    thanks for the great explanation... you're really good...

    P.S.
    Is that you posted on your Avatar? You're pretty...
    I was 15 when that pic was taken. But I've reduced the size of the original image, cut away all other persons from the picture and straightened my head a bit by rotating it. Then I mirrored the pic so it looks at whatever I am posting.

    And thanks for the compliment. It's always nice to hear I'm good...

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