1 files changed, 5 insertions, 4 deletions

diff --git a/src/irs.s b/src/irs.s
index 66ac0c2..5cccb6e 100644
--- a/src/irs.s
+++ b/src/irs.s
@@ -17,7 +17,7 @@ irs_main:
 
     @ r0 = irs_table address pointer
     @ r2 = tmp
-    @ r3 = 0           (for r3; r3 < 14; r3++)
+    @ r3 = 0    (for r3; r3 < 14; r3++)
     ldr r0, = irs_table
 irs_main_fp_search:
     @ Check that the current index is an active IRQ.
@@ -47,9 +47,8 @@ irs_main_handle_irs:
     mov r0, #1
     lsl r0, r0, r3
     strh r0, [ip, #2]
-    ldr  r1, [ip, #-0x208]
-    orr  r1, r1, r0
-    str  r1, [ip, #-0x208]
+    ldr r1, mem_irq_ack_bios @ r1 = IRQ_ACK_BIOS
+    str r0, [r1]
 
     @ Store the SPSR in one of the free registers and save it along with the
     @ return pointer.
@@ -86,3 +85,5 @@ irs_main_exit:
 
 mem_irq_base_reg:
     .word 0x04000200 @ IRQ_ENABLE
+mem_irq_ack_bios:
+    .word 0x03007FF8 @ IRQ_ACK_BIOS