diff --git a/CanSpamTransmitter.c b/CanSpamTransmitter.c
index 8d01374..91dccac 100644
--- a/CanSpamTransmitter.c
+++ b/CanSpamTransmitter.c
@@ -102,7 +102,7 @@ static eTimeEventTransmit isEventTransmitter(tCanSpamTransmitter *env) {
         env->time_CCU_HVC_Req_Msg = env->timeMs + CCU_HVC_Req_Msg_CYC;
 
         // Rolling Counter [0 - 15]
-        if (env->CCU_HVC_Req_Msg_CCU_HVC_Req_RC > 15) {
+        if (env->CCU_HVC_Req_Msg_CCU_HVC_Req_RC >= 15) {
             env->CCU_HVC_Req_Msg_CCU_HVC_Req_RC = 0;
         } else {
             ++env->CCU_HVC_Req_Msg_CCU_HVC_Req_RC;
@@ -174,12 +174,15 @@ static eTimeEventTransmit isEventTransmitter(tCanSpamTransmitter *env) {
         env->time_CCU_Msg1 = env->timeMs + CCU_Msg1_CYC;
 
         // Rolling Counter [0 - 15]
-        if (ccu_candb_tx.CCU_Msg1.CCU_MSG1_RC > 15) {
-            ccu_candb_tx.CCU_Msg1.CCU_MSG1_RC = 0;
+        if (env->CCU_Msg1_CCU_MSG1_RC >= 15) {
+            env->CCU_Msg1_CCU_MSG1_RC = 0;
         } else {
-            ++ccu_candb_tx.CCU_Msg1.CCU_MSG1_RC;
+            ++env->CCU_Msg1_CCU_MSG1_RC;
         }
 
+        ccu_candb_tx.CCU_Msg1.CCU_MSG1_RC = env->CCU_Msg1_CCU_MSG1_RC;
+
+
         // Checksum XOR8 of the data field this message
         // Checksum computed as per XOR algorithm:
         // Byte 1 XOR byte 2 .... XOR byte n-1. (n = packet length.)
@@ -217,7 +220,7 @@ static eTimeEventTransmit isEventTransmitter(tCanSpamTransmitter *env) {
         env->time_CCU_Msg3 = env->timeMs + CCU_Msg3_CYC;
 
         // Rolling Counter [0 - 15]
-        if (env->CCU_Msg3_CCU_MSG3_RC > 15) {
+        if (env->CCU_Msg3_CCU_MSG3_RC >= 15) {
             env->CCU_Msg3_CCU_MSG3_RC = 0;
         } else {
             ++env->CCU_Msg3_CCU_MSG3_RC;
diff --git a/CanSpamTransmitter.h b/CanSpamTransmitter.h
index 22f5bcc..17fb762 100644
--- a/CanSpamTransmitter.h
+++ b/CanSpamTransmitter.h
@@ -62,6 +62,7 @@ typedef struct {
     uint32_t time_CCU_AC_Ctrl;
 
     uint8_t CCU_HVC_Req_Msg_CCU_HVC_Req_RC;
+    uint8_t CCU_Msg1_CCU_MSG1_RC;
     uint8_t CCU_Msg3_CCU_MSG3_RC;
 
     bool isMute;