diff --git a/Fw/Sm/SmSignalBuffer.cpp b/Fw/Sm/SmSignalBuffer.cpp
index b088a19555..5d654649a1 100644
--- a/Fw/Sm/SmSignalBuffer.cpp
+++ b/Fw/Sm/SmSignalBuffer.cpp
@@ -6,7 +6,7 @@ namespace Fw {
     SmSignalBuffer::SmSignalBuffer(const U8 *args, FwSizeType size) : m_bufferData{} {
         FW_ASSERT(args != nullptr);
         FW_ASSERT(size <= sizeof(this->m_bufferData));
-        SerializeStatus stat = SerializeBufferBase::setBuff(args,size);
+        SerializeStatus stat = SerializeBufferBase::setBuff(args,static_cast<NATIVE_UINT_TYPE>(size));
         FW_ASSERT(FW_SERIALIZE_OK == stat,static_cast<NATIVE_INT_TYPE>(stat));
     }
 
diff --git a/config/FpConfig.h b/config/FpConfig.h
index 6623b43615..1646f92a53 100644
--- a/config/FpConfig.h
+++ b/config/FpConfig.h
@@ -278,7 +278,7 @@ typedef FwIndexType FwQueueSizeType;
 
 // Specifies the size of the buffer attached to state machine signals.
 #ifndef FW_SM_SIGNAL_BUFFER_MAX_SIZE
-#define FW_SM_SIGNAL_BUFFER_MAX_SIZE 128
+#define FW_SM_SIGNAL_BUFFER_MAX_SIZE 128  // Not to exceed size of NATIVE_UINT_TYPE
 #endif
 
 // Specifies the size of the buffer that contains the serialized command arguments.