Real Mode Assembly: Print Char to Screen without INT Instruction on Boot

Question

The following site \"Writing Boot Sector Code\" provides a sample of code that prints \'A\' to the screen when the system boots. From what I have been reading don\'t you have to

Answer 1

Basically when you call INT 10h, BIOS will execute a routine that does almost the same thing, by writing characters and their attributes to video memory. It is, however useful to know how to write and execute these routines yourself so if and when you decide to switch the CPU into 32-bit protected mode, you can still print characters to the screen because in that mode you will no longer be able to call BIOS interrupts.