diff --git a/ChangeLog b/ChangeLog
index 3bbd4e2c0d..dce32ae0dc 100755
--- a/ChangeLog
+++ b/ChangeLog
@@ -11338,4 +11338,6 @@
 	  systime_t to represent the 32- or 64-bit system timer (2016-01-21).
 	* sched/clock/clock_systimespec.c:  Fix an error in a time
 	  conversion (2016-01-21).
+	* include/nuttx/clock.h:  Get rid of clock_systimer32() and
+	  clock_systime64().  There is now only clock_systimer() (2016-01-21).
 
diff --git a/include/nuttx/clock.h b/include/nuttx/clock.h
index cc6eccd14c..f2e354725a 100644
--- a/include/nuttx/clock.h
+++ b/include/nuttx/clock.h
@@ -165,14 +165,6 @@
 #define TICK2DSEC(tick)       (((tick)+(TICK_PER_DSEC/2))/TICK_PER_DSEC) /* Rounds */
 #define TICK2SEC(tick)        (((tick)+(TICK_PER_SEC/2))/TICK_PER_SEC)   /* Rounds */
 
-/* Select the access to the system timer using its natural with */
-
-#ifdef CONFIG_SYSTEM_TIME64
-#  define clock_systimer()    clock_systimer64()
-#else
-#  define clock_systimer()    clock_systimer32()
-#endif
-
 /****************************************************************************
  * Public Types
  ****************************************************************************/
@@ -214,18 +206,8 @@ extern "C"
  */
 
 #ifdef __HAVE_KERNEL_GLOBALS
-#  ifdef CONFIG_SYSTEM_TIME64
-
-EXTERN volatile uint64_t g_system_timer;
-#define clock_systimer32()  (uint32_t)(g_system_timer & 0x00000000ffffffff)
-#define clock_systimer64() g_system_timer
-
-#  else
-
-EXTERN volatile uint32_t g_system_timer;
-#define clock_systimer32() g_system_timer
-
-#  endif
+EXTERN volatile systime_t g_system_timer;
+#  define clock_systimer() g_system_timer
 #endif
 
 /****************************************************************************
@@ -265,13 +247,13 @@ void clock_synchronize(void);
 #endif
 
 /****************************************************************************
- * Function:  clock_systimer32
+ * Function:  clock_systimer
  *
  * Description:
- *   Return the current value of the 32-bit system timer counter.  Indirect
- *   access to the system timer counter is required through this function if
- *   the execution environment does not have direct access to kernel global
- *   data
+ *   Return the current value of the 32/64-bit system timer counter.
+ *   Indirect access to the system timer counter is required through this
+ *   function if the execution environment does not have direct access to
+ *   kernel globaldata
  *
  * Parameters:
  *   None
@@ -284,34 +266,7 @@ void clock_synchronize(void);
  ****************************************************************************/
 
 #ifndef __HAVE_KERNEL_GLOBALS
-#  ifdef CONFIG_SYSTEM_TIME64
-#    define clock_systimer32()  (uint32_t)(clock_systimer64() & 0x00000000ffffffff)
-#  else
-uint32_t clock_systimer32(void);
-#  endif
-#endif
-
-/****************************************************************************
- * Function:  clock_systimer64
- *
- * Description:
- *   Return the current value of the 64-bit system timer counter.  Indirect
- *   access to the system timer counter is required through this function if
- *   the execution environment does not have direct access to kernel global
- *   data
- *
- * Parameters:
- *   None
- *
- * Return Value:
- *   The current value of the system timer counter
- *
- * Assumptions:
- *
- ****************************************************************************/
-
-#if !defined(__HAVE_KERNEL_GLOBALS) && defined(CONFIG_SYSTEM_TIME64)
-uint64_t clock_systimer64(void);
+systime_t clock_systimer(void);
 #endif
 
 /****************************************************************************
diff --git a/include/sys/syscall.h b/include/sys/syscall.h
index 87bd73faf0..c7d9b086c4 100644
--- a/include/sys/syscall.h
+++ b/include/sys/syscall.h
@@ -211,11 +211,7 @@
  * NuttX configuration.
  */
 
-#ifdef CONFIG_SYSTEM_TIME64
-#  define SYS_clock_systimer64         (__SYS_clock+0)
-#else
-#  define SYS_clock_systimer32         (__SYS_clock+0)
-#endif
+#define SYS_clock_systimer             (__SYS_clock+0)
 #define SYS_clock_getres               (__SYS_clock+1)
 #define SYS_clock_gettime              (__SYS_clock+2)
 #define SYS_clock_settime              (__SYS_clock+3)
diff --git a/sched/clock/clock_systimer.c b/sched/clock/clock_systimer.c
index 24c92b7916..c3f56a7421 100644
--- a/sched/clock/clock_systimer.c
+++ b/sched/clock/clock_systimer.c
@@ -51,8 +51,7 @@
  ****************************************************************************/
 /* See nuttx/clock.h */
 
-#undef clock_systimer32
-#undef clock_systimer64
+#undef clock_systimer
 
 /****************************************************************************
  * Private Data
@@ -63,10 +62,10 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: clock_systimer32
+ * Name: clock_systimer
  *
  * Description:
- *   Return the current value of the 32-bit system timer counter
+ *   Return the current value of the 32/64-bit system timer counter
  *
  * Parameters:
  *   None
@@ -78,57 +77,10 @@
  *
  ****************************************************************************/
 
-uint32_t clock_systimer32(void)
+systime_t clock_systimer(void)
 {
 #ifdef CONFIG_SCHED_TICKLESS
-  struct timespec ts;
-  uint64_t tmp;
-
-  /* Get the time from the platform specific hardware */
-
-  (void)up_timer_gettime(&ts);
-
-  /* Convert to a 64- then 32-bit value */
-
-  tmp = MSEC2TICK(1000 * (uint64_t)ts.tv_sec + (uint64_t)ts.tv_nsec / 1000000);
-  return (uint32_t)(tmp & 0x00000000ffffffff);
-
-#else
-
 #ifdef CONFIG_SYSTEM_TIME64
-  /* Return the current system time truncated to 32-bits */
-
-  return (uint32_t)(g_system_timer & 0x00000000ffffffff);
-
-#else
-  /* Return the current system time */
-
-  return g_system_timer;
-
-#endif
-#endif
-}
-
-/****************************************************************************
- * Name: clock_systimer64
- *
- * Description:
- *   Return the current value of the 64-bit system timer counter
- *
- * Parameters:
- *   None
- *
- * Return Value:
- *   The current value of the system timer counter
- *
- * Assumptions:
- *
- ****************************************************************************/
-
-#ifdef CONFIG_SYSTEM_TIME64
-uint64_t clock_systimer64(void)
-{
-#ifdef CONFIG_SCHED_TICKLESS
   struct timespec ts;
 
   /* Get the time from the platform specific hardware */
@@ -139,10 +91,23 @@ uint64_t clock_systimer64(void)
 
   return USEC2TICK(1000000 * (uint64_t)ts.tv_sec + (uint64_t)ts.tv_nsec / 1000);
 #else
+  struct timespec ts;
+  uint64_t tmp;
+
+  /* Get the time from the platform specific hardware */
+
+  (void)up_timer_gettime(&ts);
+
+  /* Convert to a 64- then 32-bit value */
+
+  tmp = MSEC2TICK(1000 * (uint64_t)ts.tv_sec + (uint64_t)ts.tv_nsec / 1000000);
+  return (systime_t)(tmp & 0x00000000ffffffff);
+#endif
+#else
+
   /* Return the current system time */
 
   return g_system_timer;
 
 #endif
 }
-#endif
diff --git a/syscall/syscall.csv b/syscall/syscall.csv
index 43e8e9175f..b20a2aca97 100644
--- a/syscall/syscall.csv
+++ b/syscall/syscall.csv
@@ -11,8 +11,7 @@
 "clock_getres","time.h","","int","clockid_t","struct timespec*"
 "clock_gettime","time.h","","int","clockid_t","struct timespec*"
 "clock_settime","time.h","","int","clockid_t","const struct timespec*"
-"clock_systimer32","nuttx/clock.h","!defined(__HAVE_KERNEL_GLOBALS) && !defined(CONFIG_SYSTEM_TIME64)","uint32_t"
-"clock_systimer64","nuttx/clock.h","!defined(__HAVE_KERNEL_GLOBALS) && defined(CONFIG_SYSTEM_TIME64)","uint64_t"
+"clock_systimer","nuttx/clock.h","!defined(__HAVE_KERNEL_GLOBALS)","systime_t"
 "close","unistd.h","CONFIG_NSOCKET_DESCRIPTORS > 0 || CONFIG_NFILE_DESCRIPTORS > 0","int","int"
 "closedir","dirent.h","CONFIG_NFILE_DESCRIPTORS > 0","int","FAR DIR*"
 "connect","sys/socket.h","CONFIG_NSOCKET_DESCRIPTORS > 0 && defined(CONFIG_NET)","int","int","FAR const struct sockaddr*","socklen_t"
diff --git a/syscall/syscall_clock_systimer.c b/syscall/syscall_clock_systimer.c
index b6bbc00cac..dce97f1633 100644
--- a/syscall/syscall_clock_systimer.c
+++ b/syscall/syscall_clock_systimer.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * syscall/syscall_clock_systimer.c
  *
- *   Copyright (C) 2011-2012, 2014 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2011-2012, 2014, 2016 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -60,7 +60,7 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: syscall_clock_systimer32/64
+ * Name: syscall_clock_systimer
  *
  * Description:
  *   In the kernel build, proxying for clock_systimer() must be handled
@@ -74,14 +74,7 @@
  *
  ****************************************************************************/
 
-#ifdef CONFIG_SYSTEM_TIME64
-uint64_t syscall_clock_systimer64(void)
+systime_t syscall_clock_systimer(void)
 {
-  return clock_systimer64();
+  return clock_systime();
 }
-#else
-uint32_t syscall_clock_systimer32(void)
-{
-  return clock_systimer32();
-}
-#endif
diff --git a/syscall/syscall_funclookup.c b/syscall/syscall_funclookup.c
index b1545fb4f1..8e62470103 100644
--- a/syscall/syscall_funclookup.c
+++ b/syscall/syscall_funclookup.c
@@ -99,11 +99,7 @@
  * have an address that can be included in the g_funclookup[] table.
  */
 
-#ifdef CONFIG_SYSTEM_TIME64
-uint64_t syscall_clock_systimer64(void);
-#else
-uint32_t syscall_clock_systimer32(void);
-#endif
+systime_t syscall_clock_systimer(void);
 
 /****************************************************************************
  * Pre-processor Definitions
diff --git a/syscall/syscall_lookup.h b/syscall/syscall_lookup.h
index 615d17ba87..6ad246ba5b 100644
--- a/syscall/syscall_lookup.h
+++ b/syscall/syscall_lookup.h
@@ -148,11 +148,7 @@ SYSCALL_LOOKUP(up_assert,                 2, STUB_up_assert)
  * NuttX configuration.
  */
 
-#ifdef CONFIG_SYSTEM_TIME64
-  SYSCALL_LOOKUP(syscall_clock_systimer64, 0, STUB_clock_systimer64)
-#else
-  SYSCALL_LOOKUP(syscall_clock_systimer32, 0, STUB_clock_systimer32)
-#endif
+  SYSCALL_LOOKUP(syscall_clock_systimer,  0, STUB_clock_systimer)
   SYSCALL_LOOKUP(clock_getres,            2, STUB_clock_getres)
   SYSCALL_LOOKUP(clock_gettime,           2, STUB_clock_gettime)
   SYSCALL_LOOKUP(clock_settime,           2, STUB_clock_settime)
diff --git a/syscall/syscall_stublookup.c b/syscall/syscall_stublookup.c
index 8c10723f89..ed151d246b 100644
--- a/syscall/syscall_stublookup.c
+++ b/syscall/syscall_stublookup.c
@@ -150,11 +150,7 @@ uintptr_t STUB_nanosleep(int nbr, uintptr_t parm1, uintptr_t parm2);
  * NuttX configuration.
  */
 
-#ifdef CONFIG_SYSTEM_TIME64
-uintptr_t STUB_clock_systimer64(int nbr);
-#else
-uintptr_t STUB_clock_systimer32(int nbr);
-#endif
+uintptr_t STUB_clock_systimer(int nbr);
 uintptr_t STUB_clock_getres(int nbr, uintptr_t parm1, uintptr_t parm2);
 uintptr_t STUB_clock_gettime(int nbr, uintptr_t parm1, uintptr_t parm2);
 uintptr_t STUB_clock_settime(int nbr, uintptr_t parm1, uintptr_t parm2);