1 files changed, 3 insertions, 3 deletions

diff --git a/src/irs.s b/src/irs.s
index 924441e..66ac0c2 100644
--- a/src/irs.s
+++ b/src/irs.s
@@ -47,7 +47,9 @@ irs_main_handle_irs:
     mov r0, #1
     lsl r0, r0, r3
     strh r0, [ip, #2]
-    @ TODO: IRQ_ACK_BIOS
+    ldr  r1, [ip, #-0x208]
+    orr  r1, r1, r0
+    str  r1, [ip, #-0x208]
 
     @ Store the SPSR in one of the free registers and save it along with the
     @ return pointer.
@@ -84,5 +86,3 @@ irs_main_exit:
 
 mem_irq_base_reg:
     .word 0x04000200 @ IRQ_ENABLE
-    .word 0x04000202 @ IRQ_ACK
-    .word 0x04000208 @ IRQ_CTRL