diff --git a/Inc/PwmIO.h b/Inc/PwmIO.h
index b7b4e7d..fc2d28c 100644
--- a/Inc/PwmIO.h
+++ b/Inc/PwmIO.h
@@ -8,10 +8,12 @@
 #include "stdint.h"
 
 typedef void (*PwmIOTransaction  )(void *env);
+typedef void (*PwmIOTransactionSetActivePercent  )(void *env, uint8_t percent);
 
 typedef struct {
     void *env;
     PwmIOTransaction run;
+    PwmIOTransactionSetActivePercent setActivePercent;
 } tPwmIO;