diff --git a/CHANGES b/CHANGES
index 522007fef..fc891a9f7 100644
--- a/CHANGES
+++ b/CHANGES
@@ -18,6 +18,7 @@ Bugfixes:
  - GBA BIOS: Fix misaligned CpuSet
  - Libretro: Fix problems with rumble not turning off
  - ARM7: Fix sign of unaligned LDRSH
+ - GBA BIOS: Fix CpuSet on 0x01XXXXXX addresses
 Misc:
  - Qt: Window size command line options are now supported
  - Qt: Increase usability of key mapper
diff --git a/src/gba/bios.c b/src/gba/bios.c
index a00555c1e..0a570daf0 100644
--- a/src/gba/bios.c
+++ b/src/gba/bios.c
@@ -220,7 +220,7 @@ void GBASwi16(struct ARMCore* cpu, int immediate) {
 		break;
 	case 0xB:
 	case 0xC:
-		if (cpu->gprs[0] >> BASE_OFFSET == REGION_BIOS) {
+		if (cpu->gprs[0] >> BASE_OFFSET < REGION_WORKING_RAM) {
 			GBALog(gba, GBA_LOG_GAME_ERROR, "Cannot CpuSet from BIOS");
 			return;
 		}