diff --git a/freemodbus/modbus/rtu/mbrtu.c b/freemodbus/modbus/rtu/mbrtu.c
index 963fe7d..64336be 100644
--- a/freemodbus/modbus/rtu/mbrtu.c
+++ b/freemodbus/modbus/rtu/mbrtu.c
@@ -245,7 +245,9 @@ xMBRTUReceiveFSM( void )
     BOOL            xStatus = FALSE;
     UCHAR           ucByte;
 
-    assert( eSndState == STATE_TX_IDLE );
+    if ( eSndState != STATE_TX_IDLE  ) {
+        return FALSE;
+    }
 
     /* Always read the character. */
     xStatus = xMBPortSerialGetByte( ( CHAR * ) & ucByte );
@@ -307,7 +309,9 @@ xMBRTUTransmitFSM( void )
 {
     BOOL xNeedPoll = TRUE;
 
-    assert( eRcvState == STATE_RX_IDLE );
+    if ( eRcvState != STATE_RX_IDLE  ) {
+        return FALSE;
+    }
 
     switch ( eSndState )
     {
diff --git a/idf_component.yml b/idf_component.yml
index 5ebee56..f87dc7f 100644
--- a/idf_component.yml
+++ b/idf_component.yml
@@ -1,4 +1,4 @@
-version: "1.0.17"
+version: "1.0.18"
 description: ESP-MODBUS is the official Modbus library for Espressif SoCs.
 url: https://github.com/espressif/esp-modbus
 dependencies: