diff --git a/Inc/AdcIO.h b/Inc/AdcIO.h
index 4be0d73..21ceab0 100644
--- a/Inc/AdcIO.h
+++ b/Inc/AdcIO.h
@@ -7,12 +7,10 @@
 
 #include "stdint.h"
 
-typedef void (*AdcIOStartTransaction )(void *env);
 typedef uint8_t (*AdcIOTransaction  )(void *env, uint32_t *buf, uint32_t timeout);
 
 typedef struct {
     void *env;
-    AdcIOStartTransaction start;
     AdcIOTransaction get;
 } tAdcIO;