x86 NASM 'org' directive meaning

Question

I am following this tutorial as a first foray into bootloader/OS development for x86 using NASM:

http://joelgompert.com/OS/TableOfContents.htm

And I\'m on Le

Answer 1

0000:7C00 is not equivalent to 7C00:0000. The segment part is counted in paragraphs, not bytes. Try this instead:

mov ax, 0x7c0 
mov ds, ax

Answer 2

org defines where the program in question EXPECTS to be loaded into memory. Not where it actually is loaded -- that is controlled by whoever does the loading -- but where it expects to be loaded.