diff --git a/taenzer.h b/taenzer.h
index cac0267..4e23e6f 100644
--- a/taenzer.h
+++ b/taenzer.h
@@ -3,7 +3,7 @@
 
 #include <stdint.h>
 
-typedef struct {
+typedef volatile struct {
     uint8_t homed;
     uint32_t pos;
 } taenzer_state_t;