diff --git a/arch/sim/src/up_blocktask.c b/arch/sim/src/up_blocktask.c
index 66cd893723..ad432fa021 100644
--- a/arch/sim/src/up_blocktask.c
+++ b/arch/sim/src/up_blocktask.c
@@ -94,7 +94,7 @@ void up_block_task(_TCB *tcb, tstate_t task_state)
       _TCB *rtcb = (_TCB*)g_readytorun.head;
       boolean switch_needed;
 
-      dbg("Blocking TCB=%p\n", tcb);
+      sdbg("Blocking TCB=%p\n", tcb);
 
       /* Remove the tcb task from the ready-to-run list.  If we
        * are blocking the task at the head of the task list (the
@@ -134,7 +134,7 @@ void up_block_task(_TCB *tcb, tstate_t task_state)
                */
 
               rtcb = (_TCB*)g_readytorun.head;
-              dbg("New Active Task TCB=%p\n", rtcb);
+              sdbg("New Active Task TCB=%p\n", rtcb);
 
               /* The way that we handle signals in the simulation is kind of
                * a kludge.  This would be unsafe in a truly multi-threaded, interrupt
@@ -143,7 +143,7 @@ void up_block_task(_TCB *tcb, tstate_t task_state)
 
               if (rtcb->xcp.sigdeliver)
                 {
-                  dbg("Delivering signals TCB=%p\n", rtcb);
+                  sdbg("Delivering signals TCB=%p\n", rtcb);
                   ((sig_deliver_t)rtcb->xcp.sigdeliver)(rtcb);
                   rtcb->xcp.sigdeliver = NULL;
                 }
diff --git a/arch/sim/src/up_deviceimage.c b/arch/sim/src/up_deviceimage.c
index 70dfc9cab1..ac728c7f5b 100644
--- a/arch/sim/src/up_deviceimage.c
+++ b/arch/sim/src/up_deviceimage.c
@@ -55,7 +55,7 @@
  ****************************************************************************/
 
 #ifdef VFAT_STANDALONE
-# define dbg(format, arg...) printf(format, ##arg)
+# define sdbg(format, arg...) printf(format, ##arg)
 #endif
 
 /****************************************************************************
@@ -218,7 +218,7 @@ char *up_deviceimage(void)
     ret           = inflateInit(&strm);
     if (ret != Z_OK)
       {
-        dbg("inflateInit FAILED: ret=%d msg=\"%s\"\n", ret, strm.msg ? strm.msg : "No message" );
+        sdbg("inflateInit FAILED: ret=%d msg=\"%s\"\n", ret, strm.msg ? strm.msg : "No message" );
         return NULL;
       }
 
@@ -252,7 +252,7 @@ char *up_deviceimage(void)
             case Z_DATA_ERROR:
             case Z_MEM_ERROR:
             case Z_STREAM_ERROR:
-                dbg("inflate FAILED: ret=%d msg=\"%s\"\n", ret, strm.msg ? strm.msg : "No message" );
+                sdbg("inflate FAILED: ret=%d msg=\"%s\"\n", ret, strm.msg ? strm.msg : "No message" );
                 (void)inflateEnd(&strm);
                 free(pbuffer);
                 return NULL;
diff --git a/arch/sim/src/up_exit.c b/arch/sim/src/up_exit.c
index 650403b7eb..8ab8f92cf4 100644
--- a/arch/sim/src/up_exit.c
+++ b/arch/sim/src/up_exit.c
@@ -74,7 +74,7 @@ void _exit(int status)
 {
   _TCB* tcb = (_TCB*)g_readytorun.head;
 
-  dbg("TCB=%p exitting\n", tcb);
+  sdbg("TCB=%p exitting\n", tcb);
 
   /* Remove the tcb task from the ready-to-run list.  We can
    * ignore the return value because we know that a context
@@ -113,7 +113,7 @@ void _exit(int status)
    */
 
   tcb = (_TCB*)g_readytorun.head;
-  dbg("New Active Task TCB=%p\n", tcb);
+  sdbg("New Active Task TCB=%p\n", tcb);
 
   /* The way that we handle signals in the simulation is kind of
    * a kludge.  This would be unsafe in a truly multi-threaded, interrupt
@@ -122,7 +122,7 @@ void _exit(int status)
 
   if (tcb->xcp.sigdeliver)
     {
-      dbg("Delivering signals TCB=%p\n", tcb);
+      sdbg("Delivering signals TCB=%p\n", tcb);
       ((sig_deliver_t)tcb->xcp.sigdeliver)(tcb);
       tcb->xcp.sigdeliver = NULL;
     }
diff --git a/arch/sim/src/up_releasepending.c b/arch/sim/src/up_releasepending.c
index 8a494a3542..5f25a0db6e 100644
--- a/arch/sim/src/up_releasepending.c
+++ b/arch/sim/src/up_releasepending.c
@@ -76,7 +76,7 @@ void up_release_pending(void)
 {
   _TCB *rtcb = (_TCB*)g_readytorun.head;
 
-  dbg("From TCB=%p\n", rtcb);
+  sdbg("From TCB=%p\n", rtcb);
 
   /* Merge the g_pendingtasks list into the g_readytorun task list */
 
@@ -96,7 +96,7 @@ void up_release_pending(void)
            */
 
           rtcb = (_TCB*)g_readytorun.head;
-          dbg("New Active Task TCB=%p\n", rtcb);
+          sdbg("New Active Task TCB=%p\n", rtcb);
 
           /* The way that we handle signals in the simulation is kind of
            * a kludge.  This would be unsafe in a truly multi-threaded, interrupt
@@ -105,7 +105,7 @@ void up_release_pending(void)
 
           if (rtcb->xcp.sigdeliver)
             {
-              dbg("Delivering signals TCB=%p\n", rtcb);
+              sdbg("Delivering signals TCB=%p\n", rtcb);
               ((sig_deliver_t)rtcb->xcp.sigdeliver)(rtcb);
               rtcb->xcp.sigdeliver = NULL;
             }
diff --git a/arch/sim/src/up_reprioritizertr.c b/arch/sim/src/up_reprioritizertr.c
index d4d91a88e1..f2a2b28287 100644
--- a/arch/sim/src/up_reprioritizertr.c
+++ b/arch/sim/src/up_reprioritizertr.c
@@ -97,7 +97,7 @@ void up_reprioritize_rtr(_TCB *tcb, ubyte priority)
       _TCB *rtcb = (_TCB*)g_readytorun.head;
       boolean switch_needed;
 
-      dbg("TCB=%p PRI=%d\n", tcb, priority);
+      sdbg("TCB=%p PRI=%d\n", tcb, priority);
 
       /* Remove the tcb task from the ready-to-run list.
        * sched_removereadytorun will return TRUE if we just
@@ -146,7 +146,7 @@ void up_reprioritize_rtr(_TCB *tcb, ubyte priority)
                */
 
               rtcb = (_TCB*)g_readytorun.head;
-              dbg("New Active Task TCB=%p\n", rtcb);
+              sdbg("New Active Task TCB=%p\n", rtcb);
 
               /* The way that we handle signals in the simulation is kind of
                * a kludge.  This would be unsafe in a truly multi-threaded, interrupt
@@ -155,7 +155,7 @@ void up_reprioritize_rtr(_TCB *tcb, ubyte priority)
 
               if (rtcb->xcp.sigdeliver)
                 {
-                  dbg("Delivering signals TCB=%p\n", rtcb);
+                  sdbg("Delivering signals TCB=%p\n", rtcb);
                   ((sig_deliver_t)rtcb->xcp.sigdeliver)(rtcb);
                   rtcb->xcp.sigdeliver = NULL;
                 }
diff --git a/arch/sim/src/up_unblocktask.c b/arch/sim/src/up_unblocktask.c
index bf25a14a54..ba5f5987d3 100644
--- a/arch/sim/src/up_unblocktask.c
+++ b/arch/sim/src/up_unblocktask.c
@@ -90,7 +90,7 @@ void up_unblock_task(_TCB *tcb)
     {
       _TCB *rtcb = (_TCB*)g_readytorun.head;
 
-      dbg("Unblocking TCB=%p\n", tcb);
+      sdbg("Unblocking TCB=%p\n", tcb);
 
      /* Remove the task from the blocked task list */
 
@@ -124,7 +124,7 @@ void up_unblock_task(_TCB *tcb)
               */
 
              rtcb = (_TCB*)g_readytorun.head;
-             dbg("New Active Task TCB=%p\n", rtcb);
+             sdbg("New Active Task TCB=%p\n", rtcb);
 
               /* The way that we handle signals in the simulation is kind of
                * a kludge.  This would be unsafe in a truly multi-threaded, interrupt
@@ -133,7 +133,7 @@ void up_unblock_task(_TCB *tcb)
 
               if (rtcb->xcp.sigdeliver)
                 {
-                  dbg("Delivering signals TCB=%p\n", rtcb);
+                  sdbg("Delivering signals TCB=%p\n", rtcb);
                   ((sig_deliver_t)rtcb->xcp.sigdeliver)(rtcb);
                   rtcb->xcp.sigdeliver = NULL;
                 }