diff --git a/arch/sim/src/Makefile b/arch/sim/src/Makefile
index 58355c578f..d30c045ab7 100644
--- a/arch/sim/src/Makefile
+++ b/arch/sim/src/Makefile
@@ -59,10 +59,8 @@ AOBJS = $(ASRCS:.S=$(OBJEXT))
 
 CSRCS  = sim_initialize.c sim_idle.c sim_interruptcontext.c sim_initialstate.c
 CSRCS += sim_createstack.c sim_usestack.c sim_releasestack.c sim_stackframe.c
-CSRCS += sim_exit.c sim_schedulesigaction.c sim_switchcontext.c
-CSRCS += sim_heap.c sim_uart.c sim_assert.c sim_nputs.c
-CSRCS += sim_copyfullstate.c
-CSRCS += sim_sigdeliver.c
+CSRCS += sim_exit.c sim_schedulesigaction.c sim_switchcontext.c sim_heap.c
+CSRCS += sim_uart.c sim_assert.c sim_copyfullstate.c sim_sigdeliver.c
 
 ifeq ($(CONFIG_SCHED_BACKTRACE),y)
 CSRCS += sim_backtrace.c
diff --git a/arch/sim/src/sim/sim_nputs.c b/arch/sim/src/sim/sim_nputs.c
deleted file mode 100644
index fc26282923..0000000000
--- a/arch/sim/src/sim/sim_nputs.c
+++ /dev/null
@@ -1,58 +0,0 @@
-/****************************************************************************
- * arch/sim/src/sim/sim_nputs.c
- *
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements.  See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.  The
- * ASF licenses this file to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance with the
- * License.  You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
- * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
- * License for the specific language governing permissions and limitations
- * under the License.
- *
- ****************************************************************************/
-
-/****************************************************************************
- * Included Files
- ****************************************************************************/
-
-#include <nuttx/config.h>
-#include <nuttx/arch.h>
-
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Name: up_nputs
- *
- * Description:
- *   This is a low-level helper function used to support debug.
- *
- ****************************************************************************/
-
-void up_nputs(const char *str, size_t len)
-{
-  while (len-- > 0 && *str)
-    {
-      up_putc(*str++);
-    }
-}
diff --git a/arch/sim/src/sim/sim_uart.c b/arch/sim/src/sim/sim_uart.c
index 6ebf3d8d87..6a2086538e 100644
--- a/arch/sim/src/sim/sim_uart.c
+++ b/arch/sim/src/sim/sim_uart.c
@@ -569,3 +569,19 @@ int up_putc(int ch)
 #endif
   return 0;
 }
+
+/****************************************************************************
+ * Name: up_nputs
+ *
+ * Description:
+ *   This is a low-level helper function used to support debug.
+ *
+ ****************************************************************************/
+
+void up_nputs(const char *str, size_t len)
+{
+  while (len-- > 0 && *str)
+    {
+      up_putc(*str++);
+    }
+}