If I am writing boot sector code and I want to put the 55AA right at the end making my entire file exactly 512bytes long, how would I do it?

With TASM I believe you can do something like the following:

BootSignature:
ORG Boot_Start+510
db 055h,0AAh

Where Boot_Start is the start of your code.


Thanks

On FAsm (and also NAsm), the ORG functions "correctly", so you cannot use it to jump around in the code.

You can do it like this:

times (510-($-Boot_Start)) db 0
dw 0AA55h

Sweet, thank-you.

Just out of curiosity, how do you guys know this stuff. Is it just by reading the source code and inc files?

The docs that come with fasm seem to be more of an assembly language tutorial rather than giving out the compiler specific commands.

Thanks,

...Gomer