diff --git a/mupen64plus-core/src/device/cart/cart.c b/mupen64plus-core/src/device/cart/cart.c
index 7377e5a..7164d3f 100644
--- a/mupen64plus-core/src/device/cart/cart.c
+++ b/mupen64plus-core/src/device/cart/cart.c
@@ -169,6 +169,7 @@ void read_cart_dom2(void* opaque, uint32_t address, uint32_t* value)
         cart->use_flashram = 1;
         read_flashram(&cart->flashram, address, value);
     }
+    cp0_rom_interlock(cart->cart_rom.r4300, pi_calculate_cycles(cart->cart_rom.pi, 2, 4));
 }
 
 void write_cart_dom2(void* opaque, uint32_t address, uint32_t value, uint32_t mask)
@@ -190,6 +191,9 @@ void write_cart_dom2(void* opaque, uint32_t address, uint32_t value, uint32_t ma
         cart->use_flashram = 1;
         write_flashram(&cart->flashram, address, value, mask);
     }
+    /* Mark IO as busy */
+    cart->cart_rom.pi->regs[PI_STATUS_REG] |= PI_STATUS_IO_BUSY;
+    add_interrupt_event(&cart->cart_rom.r4300->cp0, PI_INT, pi_calculate_cycles(cart->cart_rom.pi, 2, 4) / 2);
 }
 
 uint32_t cart_dom2_dma_read(void* opaque, const uint8_t* dram, uint32_t dram_addr, uint32_t cart_addr, uint32_t length)
diff --git a/mupen64plus-core/src/device/dd/dd_controller.c b/mupen64plus-core/src/device/dd/dd_controller.c
index cee1dac..703dce7 100644
--- a/mupen64plus-core/src/device/dd/dd_controller.c
+++ b/mupen64plus-core/src/device/dd/dd_controller.c
@@ -547,7 +547,11 @@ void read_dd_rom(void* opaque, uint32_t address, uint32_t* value)
 
 void write_dd_rom(void* opaque, uint32_t address, uint32_t value, uint32_t mask)
 {
+    struct dd_controller* dd = (struct dd_controller*)opaque;
     DebugMessage(M64MSG_VERBOSE, "DD ROM: %08X <- %08x & %08x", address, value, mask);
+    /* Mark IO as busy */
+    dd->pi->regs[PI_STATUS_REG] |= PI_STATUS_IO_BUSY;
+    add_interrupt_event(&dd->r4300->cp0, PI_INT, pi_calculate_cycles(dd->pi, 1, 4) / 2);
 }
 
 uint32_t dd_dom_dma_read(void* opaque, const uint8_t* dram, uint32_t dram_addr, uint32_t cart_addr, uint32_t length)