Ch 11: Real-Time Interrupts & Timer Programming

How can the execution speed or task-switching frequency of preemptive multitasking be adjusted in an assembly language kernel?

mov al, 0x36
out 0x43, al
mov ax, divisor
out 0x40, al
mov al, ah
out 0x40, al

Explain how to read disk sectors into memory using System BIOS Interrupt 13h Service 02h, including required input parameters and return registers.

mov ah, 02h
mov al, 1
mov ch, 0
mov cl, 2
mov dh, 0
mov dl, 00h
mov bx, buffer
int 13h

Read the following passage carefully and fill in the blanks with the appropriate terms in order: "BIOS sees the disks as a combination of sectors, tracks, and ________, as a raw storage device without concern to whether it is reading a file or directory. ________ provides the simplest and most powerful interface to the storage medium. However, this raw storage is meaningless to the user who needs to store his files and organize them into ________."

MOV AH, 02H
MOV AL, 01H
MOV CH, 00H
MOV CL, 02H
MOV DH, 00H
MOV DL, 80H
INT 13H