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assemblyx86-16real-modememory-segmentation

What is a paragraph (when referring to memory)


I feel silly for asking something that seems like it should be so easy to look up, but as you might guess, searching for paragraph gets a lot results that have nothing to do with what I want to know.

I've been learning assembly these past few days (writing a tiny bootloader, that sort of practice stuff) and I've seen a few references to chunks of memory called a paragraph. I have a distant memory that a paragraph is two words, but I'm really not sure. What exactly is a paragraph and what is its significance?


Solution

  • A paragraph is 16 bytes. It's relevant primarily (if not exclusively) in x86 real mode, where it's the distance between two addresses you get when you increment/decrement a segment register by one.