Read linux source code and practices

Read the linux source code and practices-general Linux technology-Linux programming and kernel information. The following is a detailed description. Next we will look at a piece of code: this code will be the beginning of an operating system.

BOOTSEG = 0x07c0

Entry start
Start:
Jmpi go, BOOTSEG
Go: mov ax, cs
Mov ds, ax
Mov es, ax
Mov [msg1 + 17], ah
Mov cx, #20
Mov dx, #0x1004
Mov bx, # 0x00c
Mov bp, # msg1
Mov ax, #0x1301
Int 0x10
Loop0: jmp loop0
Msg1:. ascii "Loading system ..."
. Byte 13, 10
Org 1, 510
. Word 0xAA55

Although it is a little short, but do something accomplished first, you will be more interested in learning it.

Compile as follows:

(The operating system I use is ubuntu: I suddenly found that linux is really an operating system designed for programmers, which is really convenient to use .)

As86-0-a-o boot. o boot. s
Ld86-0-a-o boot. o
Dd bs = 32 if = boot of = bootseg skip = 1
Dd if = bootseg of = boot. img bs = 512 count = 2880

We can see that there is a boot. imgfile under the file, and then we will install virtualbox on the system, and then use the Administrator

Sudo virtualbox

Run it, create a system, load the soft drive, and then start the OS.