diff --git a/external/c-modules/aes256ctr/micropython.mk b/external/c-modules/aes256ctr/micropython.mk
index 9e10bb03..88eb276f 100644
--- a/external/c-modules/aes256ctr/micropython.mk
+++ b/external/c-modules/aes256ctr/micropython.mk
@@ -2,7 +2,7 @@
 # Pure ASM version of AES-256 for CTR mode only
 #
 
-ifeq ($(BOARD), COLDCARD)
+ifdef BOARD
 
 SRC_USERMOD += $(USERMOD_DIR)/aes_256_ctr.o
 SRC_USERMOD += $(USERMOD_DIR)/module.c