diff --git a/can-halal.h b/can-halal.h
index c1c5504..8351424 100644
--- a/can-halal.h
+++ b/can-halal.h
@@ -19,6 +19,9 @@
 #elif defined(STM32H7)
 #include "stm32h7xx_hal.h"
 #define FTCAN_IS_FDCAN
+#ifndef FTCAN_NUM_FILTERS
+    #error "Please configure the number of filters in CubeMX, and then add a compiler define for FTCAN_NUM_FILTERS"
+#endif
 #else
 #error "Couldn't detect STM family"
 #endif