x0.asm

来自「这是一个符合posix.13 pse51的实时内核」· 汇编 代码 · 共 61 行

; Project: 	HARTIK 3.0      				
; Description:  Hard Real TIme Kernel for 386 & higher machines 
; Author:	Gerardo Lamastra			
; Date:		9/5/96 						
; Revision:	Beta 1.0

;
; The first things to do when an X application starts :
; Set up segment registers & stack; then execute startup code
; When the application returns the gate-jmp make us return to RM 
; through X interface!
;

.386P
.MODEL FLAT

; Use X standard GDT selectors

INCLUDE sel.inc

EXTRN __startup : NEAR
EXTRN __stkbase : DWORD
EXTRN __stktop  : DWORD

pmstack	SEGMENT STACK 
base	label	near
	dd 	4096 dup(0)
tos	label	near	
pmstack	ENDS

.code

PUBLIC		_cstart_

_cstart_:	; For test print a purple 1 on 3rd line!
		;mov	ax,X_FLATDATA_SEL
		;mov	ds,ax
		;mov	esi,0B8000H
		;add	esi,480
		;mov	byte ptr ds:[esi],'1'
		;mov	byte ptr ds:1[esi],5
		
		mov	ax,PM_APPLDATA_SEL
		mov	ds,ax 
		mov	es,ax
		mov	ss,ax
		mov	ax,X_FLATDATA_SEL
		mov	fs,ax 
		mov	esp,OFFSET tos
		mov	__stkbase,OFFSET base
		mov	__stktop,OFFSET tos
		
		call 	__startup
		
		
		db	0eah		   ; Direct gate jmp
		dd	0		  
		dw	X_RM_BACK_GATE

end	_cstart_