diff --git a/Source/HBIOS/Makefile b/Source/HBIOS/Makefile
index a8ff13db..0cc78bf9 100644
--- a/Source/HBIOS/Makefile
+++ b/Source/HBIOS/Makefile
@@ -42,7 +42,7 @@ else
 	BIOS=wbw
 endif
 
-ifeq ($(ROM_PLATFORM),S100)
+ifeq ($(ROM_PLATFORM),SZ180)
 	HWMON=sz180mon.bin
 else
 	HWMON=hwmon.bin