diff --git a/arch/sim/src/up_blockdevice.c b/arch/sim/src/up_blockdevice.c
index 1146e41824..d91d121ace 100644
--- a/arch/sim/src/up_blockdevice.c
+++ b/arch/sim/src/up_blockdevice.c
@@ -83,5 +83,5 @@
 
 void up_registerblockdevice(void)
 {
-  rd_register(0, (ubyte*)up_deviceimage(), NSECTORS, LOGICAL_SECTOR_SIZE, TRUE);
+  ramdisk_register(0, (ubyte*)up_deviceimage(), NSECTORS, LOGICAL_SECTOR_SIZE, TRUE);
 }