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Copy edited. Removed meta information (this is implied).
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Peter Mortensen
Peter Mortensen
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I know that BIOS loads its first instruction from 0xFFFFFFF0, but why this specific address? I've a bunch of questions, and hope you can help me with some of them, at least.

My questions:

  • Why is the first BIOS instruction located at the "top" of a 4GB4 GB RAM?
  • What would happen if my computer only has 1GB1 GB of RAM?
  • What about systems with more than 4GB4 GB of RAM (e.g: 8GBfor example, 16GB8 GB, 16 GB, etc.)?
  • Why is stack the stack initialized with some value (in this case, a value located at 0xFFFFFFF0)?

I've read about that this afternoon, and I still don't get it, please help me.

I know that BIOS loads its first instruction from 0xFFFFFFF0, but why this specific address? I've a bunch of questions, hope you can help me with some of them, at least.

My questions:

  • Why is the first BIOS instruction located at the "top" of a 4GB RAM?
  • What would happen if my computer only has 1GB of RAM?
  • What about systems with more than 4GB of RAM (e.g: 8GB, 16GB, etc.)?
  • Why is stack the initialized with some value (in this case, a value located at 0xFFFFFFF0)?

I've read about that this afternoon and I still don't get it, please help me.

I know that BIOS loads its first instruction from 0xFFFFFFF0, but why this specific address? I've a bunch of questions and hope you can help me with some of them, at least.

My questions:

  • Why is the first BIOS instruction located at the "top" of a 4 GB RAM?
  • What would happen if my computer only has 1 GB of RAM?
  • What about systems with more than 4 GB of RAM (for example, 8 GB, 16 GB, etc.)?
  • Why is the stack initialized with some value (in this case, a value located at 0xFFFFFFF0)?

I've read about that this afternoon, and I still don't get it.

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edit approved Oct 19, 2015 at 16:05
psmears
edit approved Oct 19, 2015 at 16:05
psmears
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Why is the first BIOS instruction is located at 0xFFFFFFF0 ("top" of RAM)?

I know that BIOS load it'sloads its first instruction from 0xFFFFFFF0, but why this specific address? I've a bunch of questions, hope you can help me with some of them, at least.

My questions:

  • Why is the first BIOS instruction is located at the "top" of a 4GB RAM?
  • What would happen if my computer has only has 1GB of RAM?
  • What about systems with more than 4GB of RAM (e.g: 8GB, 16GB, etc.)?
  • Why is stack the initialized with some value (in this case, a value located at 0xFFFFFFF0)?

I've read about that this afternoon and I still didn'tdon't get it, please help me.

Why the first BIOS instruction is located at 0xFFFFFFF0 ("top" of RAM)?

I know that BIOS load it's first instruction from 0xFFFFFFF0, but why this specific address? I've a bunch of questions, hope you can help me with some of them, at least.

My questions:

  • Why the first BIOS instruction is located at the "top" of a 4GB RAM?
  • What would happen if my computer has only 1GB of RAM?
  • What about systems with more than 4GB of RAM (e.g: 8GB, 16GB, etc.)?
  • Why is stack initialized with some value (in this case, a value located at 0xFFFFFFF0)?

I've read about that this afternoon and I still didn't get it, please help me.

Why is the first BIOS instruction located at 0xFFFFFFF0 ("top" of RAM)?

I know that BIOS loads its first instruction from 0xFFFFFFF0, but why this specific address? I've a bunch of questions, hope you can help me with some of them, at least.

My questions:

  • Why is the first BIOS instruction located at the "top" of a 4GB RAM?
  • What would happen if my computer only has 1GB of RAM?
  • What about systems with more than 4GB of RAM (e.g: 8GB, 16GB, etc.)?
  • Why is stack the initialized with some value (in this case, a value located at 0xFFFFFFF0)?

I've read about that this afternoon and I still don't get it, please help me.

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Fernando Paladini
Fernando Paladini
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Why the first BIOS instruction is located at 0xFFFFFFF0 ("top" of RAM)?

I know that BIOS load it's first instruction from 0xFFFFFFF0, but why this specific address? I've a bunch of questions, hope you can help me with some of them, at least.

My questions:

  • Why the first BIOS instruction is located at the "top" of a 4GB RAM?
  • What would happen if my computer has only 1GB of RAM?
  • What about systems with more than 4GB of RAM (e.g: 8GB, 16GB, etc.)?
  • Why is stack initialized with some value (in this case, a value located at 0xFFFFFFF0)?

I've read about that this afternoon and I still didn't get it, please help me.