diff --git a/fox32rom.def b/fox32rom.def
index fe27b97..5d98c2b 100644
--- a/fox32rom.def
+++ b/fox32rom.def
@@ -79,6 +79,7 @@ ryfs_get_size:                            jmp [0xF0045018]
 ryfs_get_file_list:                       jmp [0xF004501C]
 ryfs_tell:                                jmp [0xF0045020]
 ryfs_write:                               jmp [0xF0045024]
+is_romdisk_available:                     jmp [0xF0045028]
 
 ; memory copy/compare jump table
 copy_memory_bytes:                        jmp [0xF0046000]
diff --git a/main.asm b/main.asm
index a48a093..054e2ef 100644
--- a/main.asm
+++ b/main.asm
@@ -297,6 +297,7 @@ poweroff_wait:
     data.32 ryfs_get_file_list
     data.32 ryfs_tell
     data.32 ryfs_write
+    data.32 is_romdisk_available
 
     ; memory copy/compare jump table
     org.pad 0xF0046000