diff --git a/arch/avr/src/at32uc3/at32uc3_timerisr.c b/arch/avr/src/at32uc3/at32uc3_timerisr.c
index b12f8e2642..160c3e6b37 100644
--- a/arch/avr/src/at32uc3/at32uc3_timerisr.c
+++ b/arch/avr/src/at32uc3/at32uc3_timerisr.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/avr/src/at32uc3/at32uc3_timerisr.c
  *
- *   Copyright (C) 2010 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2010, 2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -61,12 +61,12 @@
  * setting that defaults to 100 (100 ticks per second = 10 MS interval).
  *
  * However, the AVR RTC does not support that default value well and so, we
- * will insist that default is over-ridden by CONFIG_MSEC_PER_TICK in the
- * configuration file.  Further, we will insist that CONFIG_MSEC_PER_TICK
- * have the value 8 (see reasoning below).
+ * will insist that default is over-ridden by CONFIG_USEC_PER_TICK in the
+ * configuration file.  Further, we will insist that CONFIG_USEC_PER_TICK
+ * have the value 10000 (see reasoning below).
  */
 
-#if defined(CONFIG_MSEC_PER_TICK) && CONFIG_MSEC_PER_TICK != 10
+#if defined(CONFIG_USEC_PER_TICK) && CONFIG_USEC_PER_TICK != 10000
 #  error "Only a 100KHz system clock is supported"
 #endif
 
diff --git a/arch/avr/src/at90usb/at90usb_timerisr.c b/arch/avr/src/at90usb/at90usb_timerisr.c
index a6e82b6043..9bd4514e94 100644
--- a/arch/avr/src/at90usb/at90usb_timerisr.c
+++ b/arch/avr/src/at90usb/at90usb_timerisr.c
@@ -56,7 +56,7 @@
  ****************************************************************************/
 
 /* The CPU frequency is given by BOARD_CPU_CLOCK (defined in board.h).  The
- * desired interrupt frequency is given by CONFIG_MSEC_PER_TICK.  An unscaled
+ * desired interrupt frequency is given by CONFIG_USEC_PER_TICK.  An unscaled
  * ideal match is given by:
  *
  *   CLOCK = CPU_CLOCK / DIVISOR                      # CPU clocks/sec
diff --git a/arch/avr/src/atmega/atmega_timerisr.c b/arch/avr/src/atmega/atmega_timerisr.c
index 4c3ada87b1..069935fb05 100644
--- a/arch/avr/src/atmega/atmega_timerisr.c
+++ b/arch/avr/src/atmega/atmega_timerisr.c
@@ -56,7 +56,7 @@
  ****************************************************************************/
 
 /* The CPU frequency is given by BOARD_CPU_CLOCK (defined in board.h).  The
- * desired interrupt frequency is given by CONFIG_MSEC_PER_TICK.  An unscaled
+ * desired interrupt frequency is given by CONFIG_USEC_PER_TICK.  An unscaled
  * ideal match is given by:
  *
  *   CLOCK = CPU_CLOCK / DIVISOR                      # CPU clocks/sec
diff --git a/arch/rgmp/src/rgmp.c b/arch/rgmp/src/rgmp.c
index 495c5e05c9..652e11cca0 100644
--- a/arch/rgmp/src/rgmp.c
+++ b/arch/rgmp/src/rgmp.c
@@ -46,6 +46,8 @@
 #include <nuttx/arch.h>
 #include <nuttx/sched.h>
 #include <nuttx/kmalloc.h>
+#include <nuttx/clock.h>
+
 #include <semaphore.h>
 #include <queue.h>
 #include <stdlib.h>
@@ -55,8 +57,8 @@
 int nest_irq = 0;
 
 // the default time is 10ms
-#ifdef CONFIG_MSEC_PER_TICK
-const unsigned int rtos_tick_time = CONFIG_MSEC_PER_TICK;
+#ifdef MSEC_PER_TICK
+const unsigned int rtos_tick_time = MSEC_PER_TICK;
 #else
 const unsigned int rtos_tick_time = 10;
 #endif