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Altera_Forum's avatar
Altera_Forum
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14 years ago

Difference between reset vector and exception vector

I am a beginer! so i don't understand about between two vectors!

Can you show me the difference between two vectors?:(

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  • Altera_Forum's avatar
    Altera_Forum
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    Exception is something which will cause your processor to skip the normal operation (i.e. it'll stop in its tracks) and jump to a pre fixed location in memory. For instance resetting some of the ARM cores will cause a 'jump' to 0x0 or to 0xFFFF0000 (depending on a setting).

    So there you see, reset is just another exception albiet an important one as it is used to start from a known state (although there is not much that is available at this state and basically a lot of set up like things have to be done here).

    The reason it is called a vector is because it has a certain direction. From your high school physics you may be remember that a vector is always directional and since these exceptions (including the reset) takes the program counter (in effect the processor) to a certain location in memory (hence in a certain direction) they are called vectors.