diff --git a/CHANGES b/CHANGES
index 014bddd65..c44b50efe 100644
--- a/CHANGES
+++ b/CHANGES
@@ -8,6 +8,7 @@ Bugfixes:
  - Qt: Fix font size in memory viewer
  - Qt: Fix a crash in the memory viewer
  - Libretro: Fix problems with rumble not turning off
+ - GBA BIOS: Fix CpuSet on 0x01XXXXXX addresses
 Misc:
  - GBA Audio: Implement missing flags on SOUNDCNT_X register
 
diff --git a/src/gba/bios.c b/src/gba/bios.c
index 9ea5b5dc9..ff2ee81be 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;
 		}