diff --git a/src/emu/cpu/z80/z80.c b/src/emu/cpu/z80/z80.c
index 5a64b86caa7..04019447093 100644
--- a/src/emu/cpu/z80/z80.c
+++ b/src/emu/cpu/z80/z80.c
@@ -330,7 +330,7 @@ static const UINT8 cc_ed[0x100] = {
 static const UINT8 cc_xy[0x100] = {
  4, 4, 4, 4, 4, 4, 4, 4, 4,15, 4, 4, 4, 4, 4, 4,
  4, 4, 4, 4, 4, 4, 4, 4, 4,15, 4, 4, 4, 4, 4, 4,
- 4,14,20,10, 9, 9, 9, 4, 4,15,20,10, 9, 9, 9, 4,
+ 4,14,20,10, 9, 9,11, 4, 4,15,20,10, 9, 9,11, 4,
  4, 4, 4, 4,23,23,19, 4, 4,15, 4, 4, 4, 4, 4, 4,
  4, 4, 4, 4, 9, 9,19, 4, 4, 4, 4, 4, 9, 9,19, 4,
  4, 4, 4, 4, 9, 9,19, 4, 4, 4, 4, 4, 9, 9,19, 4,
@@ -3324,7 +3324,7 @@ static void take_interrupt(z80_state *z80)
 				PUSH(z80, pc);
 				z80->PCD = irq_vector & 0x0038;
 				/* RST $xx + 2 cycles */
-				z80->icount -= z80->cc_op[z80->PCD] + z80->cc_ex[z80->PCD];
+				z80->icount -= z80->cc_op[z80->0xff] + z80->cc_ex[z80->0xff];
 				break;
 		}
 	}