diff --git a/kernel/intr.asm b/kernel/intr.asm
index 8da59e2..666c3c3 100644
--- a/kernel/intr.asm
+++ b/kernel/intr.asm
@@ -1,23 +1,15 @@
-; out	ds:si	copy of interrupt table
 ivt_backup:
-  push ax
-  push cx
-  push di ; backup original value
   push ds
-  mov ax, 0x80
-  call malloc
-  push di
-  mov cx, 0x80
-  mov ax, cs
+  push es
+  xor ax, ax
+  mov ds, ax
   mov es, ax
-  mov si, 0x0000
-  mov ds, si
-  rep movsb
-  pop si ; this was di after malloc
+  mov si, ax
+  mov di, 0x0100 ; int 0x40 address
+  mov cx, 0x0040 ; 0x20 interrupts * 2 words
+  repe movsw
+  pop es
   pop ds
-  pop di ; restore original di
-  pop cx
-  pop ax
   ret
 
 ; set item in interrupt vector table
@@ -34,7 +26,7 @@ ivt_set:
   sal bx,1
 
   mov [es:bx], dx
-  mov [es:bx+2], ds
+  mov [es:bx+2], cs
 
   pop ax
   pop es
diff --git a/kernel/main.asm b/kernel/main.asm
index 30640e6..bfe8dd7 100644
--- a/kernel/main.asm
+++ b/kernel/main.asm
@@ -4,18 +4,51 @@ org 0x0000
 
 _startup:
   mov ax, cs
+  mov ds, ax
+  mov es, ax
   mov ss, ax
   mov sp, 0x0000
 main:
-  mov ax, cs
+  xor ax, ax
   mov ds, ax
+  mov si, ax
+  mov cx, ax
 
-  call heap_init
-  call ivt_backup
   call debug_init
-
   int 0x2E
 
+  call ivt_backup
+
+  xor ax, ax
+  mov ds, ax
+  mov es, ax
+  xor cx, cx
+  mov si, ax
+.loop:
+  mov ax, cx
+  call kprint8
+  mov al, '='
+  call kputc
+  lodsw
+  xchg ax, dx
+  lodsw
+  call kprint16
+  mov al, ':'
+  call kputc
+  xchg ax, dx
+  call kprint16
+  mov al, ' '
+  call kputc
+  inc cx
+  test cx, 0x0003
+  jnz .loop
+  mov al, 0x0A
+  call kputc
+  mov al, 0x0D
+  call kputc
+  cmp cx, 0x0060
+  jl .loop
+
 .halt:
   hlt
   jmp .halt