pm3.asm

cxzv dvsdsd sd fsdf sdf sd f

include debug.mac
.386P              
descr struc 
 limit  dw 0
 base_l dw 0                        
 base_m db 0
 attr_l db 0
 attr_2 db 0      
 base_h db 0             
descr ends   

trap struc 
 offs_l dw 0
 sel    dw 16
 rsrv   db 0
 attr   db 8Fh
 offs_h dw 0
trap ends 
       
intr struc
 ioffs_l dw 0            
 isel    dw 16
 irsrv   db 0
 iattr   db 8Eh
 ioffs_h dw 0
intr ends
       
data segment use16
 gdt_null descr <0,0,0,0,0,0>  
 gdt_data descr <data_size-1,0,0,92h>
 gdt_code descr <code_size-1,,,98h>
 gdt_stack descr <255,0,0,92h>
 gdt_screen descr <4095,8000h,0Bh,92,0,0> 
 gdt_size=$-gdt_null        
                  
 idt label word   
 trap 10 dup (<dummy_exc>)
 trap <exc_0Ah>          
 trap <exc_0Bh>          
 trap <exc_0Ch>          
 trap <exc_0Dh>          
 trap <exc_0Eh>
 trap 17 dup (<dummy_exc>)
         
 idt_08 intr <new_08>
 idt_size=$-idt         
                            
 pdescr  dq 0               
 mes     db 27,'[31;42m Back To Real Mode!  ',27,'[0m$';(21)  
 tblhex  db '0123456789ABCDEF'
 string  db '**** ****_**** ****_**** ****'
 len=$-string           
 home_sel  dw home       
           dw 10h  
 mark_08h  dw 480 
 color_08h db 71h 
 time_08h   db 0            
 data_size=$-gdt_null   
data ends                   
                            
text segment 'code' use16   
 assume cs:text,ds:data     
 begin label word
          
 exc_0Ah proc
    pop eax
    pop eax
    mov si,offset string+5
    debug   
    mov ax,0Ah
    jmp dword ptr home_sel
 exc_0Ah endp
          
 exc_0Bh proc
    pop eax
    pop eax
    mov si,offset string+5
    debug   
    mov ax,0Bh 
    jmp dword ptr home_sel
 exc_0Bh endp            
              
 exc_0Ch proc 
    pop eax
    pop eax
    mov si,offset string+5
    debug   
    mov ax,0Ch
    jmp dword ptr home_sel
 exc_0Ch endp                       
              
 exc_0Dh proc 
    pop eax
    pop eax
    mov si,offset string+5
    debug   
    mov ax,0Dh 
    jmp dword ptr home_sel
 exc_0Dh endp 
              
 exc_0Eh proc            
    pop eax
    pop eax
    mov si,offset string+5
    debug   
    mov ax,0Eh
    jmp dword ptr home_sel
 exc_0Eh endp 
              
 dummy_exc proc
    pop eax
    pop eax
    mov si,offset string+5
    debug   
    mov ax,1111h
    jmp dword ptr home_sel
 dummy_exc endp 
 new_08 proc   
    push ax    
    push bx    
    test time_08h,03     
    jnz skip     
    mov al,21h   
    mov ah,color_08h
    mov bx,mark_08h 
    mov es:[bx],ax  
    add mark_08h,2   
  skip: inc time_08h 
        mov al,20h  
        out 20h,al  
        pop bx      
        pop ax      
        db 66h      
        iret        
 new_08 endp        
                    
                    
 main proc        
      xor eax,eax           
      mov ax,data           
      mov ds,ax             
                               
      shl eax,4             
      mov ebp,eax           
      mov bx,offset gdt_data
      mov [bx].base_l,ax    
      rol eax,16            
      mov [bx].base_m,al    
                            
      xor eax,eax                   
      mov ax,cs             
      shl eax,4             
      mov bx,offset gdt_code
      mov [bx].base_l,ax    
      rol eax,16            
      mov [bx].base_m,al
                  
      xor eax,eax 
      mov ax,ss   
      shl eax,4   
      mov bx,offset gdt_stack
      mov [bx].base_l,ax       
      rol eax,16  
      mov [bx].base_m,al 
                             
      mov dword ptr pdescr+2,ebp
      mov word ptr pdescr,gdt_size-1
      lgdt pdescr         
                          
      cli                           
      mov al,8Fh
      out 70h,al
      jmp $+2
      mov al,05h
      out 71h,al
       
      mov dx,20h
      mov al,11h
      out dx,al
      jmp $+2
      inc dx             
      mov al,20h
      out dx,al
      jmp $+2
      mov al,4
      out dx,al
      jmp $+2
      mov al,1
      out dx,al
      mov al,0FEh
      out dx,al
         
      mov dx,0A1h
      mov al,0FFh
      out dx,al
         
      mov word ptr pdescr,idt_size-1
      xor eax,eax
      mov ax,offset idt
      add eax,ebp
      mov dword ptr pdescr+2,eax
      lidt pdescr   
                        
      mov eax,cr0
      or eax,1              
      mov cr0,eax
                 
      db 0EAh
      dw offset continue
      dw 16     
           
      continue: mov ax,8       
                mov ds,ax           
                         
                mov ax,24 
                mov ss,ax
                         
                mov ax,32
                mov es,ax
                         
                mov al,0h
                out 70h,al
                sti
                                
                mov cx,300
                mov bx,2720
                mov dx,3001h  
          xxxx: push cx  
                mov cx,0 
          zzzz: loop zzzz
                mov es:[bx],dx
                inc dl   
                add bx,2 
                pop cx   
                loop xxxx
                mov ax,0FFFFh
          home: mov si,offset string         
                debug
                
                mov si,offset string
                mov cx,len
                mov ah,74h
                mov di,1600
           scr: lodsb
                stosw
                loop scr
                         
                mov al,0FEh
                out 64h,al
                hlt                        
                              
                              
        return: mov ax,data    
                mov ds,ax     
                mov ax,stk    
                mov ss,ax         
                mov sp,256
                          
                mov al,0B8h
                out 21h,al
                mov al,9Dh
                out 0A1h,al
                                
                sti      
                mov al,0      
                out 70h,al    
                              
                mov ah,09h    
                mov dx,offset mes
                int 21h       
                         
                mov ax,4C00h
                int 21h  
 main endp               
 code_size=$-main        
 text ends               
 stk segment stack 'stack'
     db 256 dup ('^')    
 stk ends                      
                         
 end main