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Code: Select all

procedure Main(); stdcall;
begin
  cls(0);
  WriteStr(0,0,'Hello World',4);
  init_idt;
	init_pic;
	init_timer(100);

  asm
    sti
  end;

  LIST('/'); // <----- Floppy Read List ok
  FloppyReset(0);

  While True do
  begin
  end;

end;

procedure keyboard_callback();
var
 Scancode:byte;
begin
  if (ReadPortB($64) and $1)=1 then
   begin
     Scancode:=ReadPortB($60);
     case Scancode of
     2:begin
       LIST('/');  // <----- Floppy Read List error
      end;

   end;
end;

Code: Select all

const
	PIC1 = $20;
	PIC2 = $A0;
	ICW1 = $11;
	ICW4 = $01;
	
	
type

 TDWORD = record
   case Byte of
   0:(Value32:DWORD);
   1:(LoWord, HiWord: WORD);
 end;

TIDTEntry = packed record
		base_low  : WORD;
                selector  : WORD;
                always_0  : BYTE;
                flags     : BYTE;
                base_high : WORD;
	end;

	TIDTPtr = packed record
		limit : word;
		base : LongWord;
	end;

var
	IDTTables : array[0..255] of TIDTEntry;
	IDTPtr : TIDTPtr;

procedure setup_int(Number : Byte; Base : TDWord; Selector : Word; Flags : Byte); forward;
procedure init_idt; forward;
procedure init_pic; forward;


procedure keys_isr(); register; assembler;
asm
  pushad
  push gs
  push fs
  push es
  push ds

  
  call keyboard_callback

  mov dx, $20
  mov al, $20
  out dx, al

  pop ds
  pop es
  pop fs
  pop gs
  popad
  iretd
end;

procedure timer_isr(); register; assembler;
asm
  pushad
  push gs
  push fs
  push es
  push ds


  call TimerHandler

  mov dx, $20
  mov al, $20
  out dx, al

  pop ds
  pop es
  pop fs
  pop gs
  popad
  iretd
end;


procedure floppy_isr(); register; assembler;
asm
  pushad
  push gs
  push fs
  push es
  push ds


  call FloppyHandler

  mov dx, $20
  mov al, $20
  out dx, al

  pop ds
  pop es
  pop fs
  pop gs
  popad
  iretd

 end;

procedure  unknown_interrupt_isr(); register; assembler;
asm
  pushad
  push gs
  push fs
  push es
  push ds

  mov dx, $20
  mov al, $20
  out dx, al 

  pop ds
  pop es
  pop fs
  pop gs
  popad
  iretd
end;

procedure setup_int(Number : Byte; Base : TDWord; Selector : Word; Flags : Byte);
begin
         IDTTables[Number].base_high:= Base.HiWord;
         IDTTables[Number].base_low:= (Base.LoWord );        //  and $0000FFFF
         IDTTables[Number].selector:= Selector;
         IDTTables[Number].flags:= Flags;
         IDTTables[Number].always_0:= $00;
end;

procedure Init_idt;
var
	i:integer;
begin
	for i:=0 to 255 do
	begin
		setup_int(i, TDWord(@unknown_interrupt_isr), $08,$8E);
	end;
	setup_int(32, TDWORD(@timer_isr), $08,$8E);
	setup_int(33, TDWORD(@keys_isr), $08,$8E);
	setup_int(38, TDWORD(@floppy_isr), $08,$8E);
	IDTPtr.limit := (SizeOf(TIDTEntry)*256)-1;
	IDTPtr.base := DWord(@IDTTables);
	asm
		lidt [IDTPtr]
  end;
end;

procedure init_pic;
begin
	WritePortB(PIC1, ICW1);
	WritePortB(PIC2, ICW1);
	WritePortB(PIC1 + 1, pic1);
	WritePortB(PIC2 + 1, pic2);
	WritePortB(PIC1 + 1, 4);
	WritePortB(PIC2 + 1, 2);
	WritePortB(PIC1 + 1, ICW4);
	WritePortB(PIC2 + 1, ICW4);
	WritePortB(PIC1 + 1, 0);
	WritePortB(PIC2 + 1, 0);
end;

Code: Select all

procedure Main(); stdcall;
begin
  cls(0);
  WriteStr(0,0,'Hello World',4);
  init_idt;
 //	init_pic;
	init_timer(100);

  asm
    sti
  end;

  LIST('/'); // <----- List ok
  FloppyReset(0);

  While True do
  begin
     keyboard_callback();   //<----   List OK
  end;

end;