Printing to the screen without a db: Difference between revisions

Note: this macro is designed to be used in [[real mode]] only, since it uses [[BIOS]] functions.

 

print_string: ; Null terminated string in SI.

pusha ; Push all registers

call print_string ; Print it out using the print_string function.

%endmacro

 

Now you can use '''print''' as if it were a function or instruction in your OS like so (note, you don't want to use this in a bootloader, it messes with the data section and I don't know how to place the boot signature at the end of the data section and still pad out to 512 bytes):

 

print 'Printing without a db in NASM!',0Dh,0Ah ; Print out a little message!

 

By the way, a little feature of NASM is the usage of the ` (back quote) character to contain a string that can use C-style escape codes like \n. It's nice and helpful.