OSDev.org

Code: Select all

00023657526i[CPU  ] BxError: instruction with op1=0xfe
00023657526i[CPU  ] nnn was 4
00023657526i[CPU  ] WARNING: Encountered an unknown instruction (signalling illegal instruction):

Code: Select all

/* setup_interrupts()
 * sets up some IRQ handlers, etc.
 */
void setup_interrupts(void)
{
   disable_ints();   /* no interruptions */

   /* init the PICs and remap them so they start at 0x20 */
   init_pics(0x20, 0x28);

   /* and now set up some interrupt handlers */
   changeISR(0x21, (void *)int_irq1);
   enable_irq(1);
   enable_ints();
   
   printk("Keyboard enabled\n");
   printk("Interrupts enabled\n");
}

void kmain(void)
{
...
...
/* set up interrupt stuff */
            printk("Setting up interrupts...\n");
   setup_interrupts();
   printk("Remapped the PICs: IRQs starting at 0x20\n");
         
   idle();   /* keep doing nothing */
}

/* idle()
 * function does nothing
 */
void idle(void)
{
   printk("\nidling...\n");
   while(1)
   {
      if (counter > 10)
      {
         printk("\ncounter\n");
         counter = 0;
      }
   }
   
}

Code: Select all

int_irq1:
   EXTERN kbd_handler 
   
   cli   ; disable interrupts while processing
   
   call save   ; save registers
   call kbd_handler   ; call the handler
   call masterEOI   ; send EOI to master
   call restore   ; restore registers
      
   sti   ; reenable interrupts
   iretd

save:
   ; save some registers
   pushad
   push ds
   push es
   push fs
   push gs
   
   mov eax, DS_SELECTOR
   mov ds, eax
   mov es, eax
   mov fs, eax
   mov gs, eax

   ret

restore:
   ; restore saved registers
   pop gs
   pop fs
   pop es
   pop ds
   popad
   
   ret

Code: Select all

int counter = 0;

void kbd_handler(void)
{
   int i;

   i = inb(0x60);
   counter++;
}