OSDev.org

I dont get it. I'm just trying to display a simple string to the screen. I found a working bootsector that accually displays a message to my screen when it boots. I removed everything but the function that writes to the screen. It dosn't work ??? ??? ??? what am i missing? i'm testing he function under dos.

are you sure some of what you removed wasn't some initialization code that's required to write to the screen? Perhaps you removed the lines of code that set ES to 0xB800 (if it writes characts directly to the screen). If it uses BIOS interrupts then maybe you removed the lines of code that set DS to 0x7c0 so that it can GET TO the string you are displaying (7c0 is the location of sector 1 that is automatically loaded by the BIOS on startup.)

i dont think it could be that because i'm just running a simple program that only has that bios function in DOS. First i'm just trying to get this to work in DOS, then when it works in DOS then set up what you are talking about for boot or OS.