8052 context switch/interrupt integration; pthread arg setup changed

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@60 42af7a65-404d-4744-a932-0658087f49c3

18 files changed, 333 insertions, 139 deletions

diff --git a/nuttx/Documentation/NuttX.html b/nuttx/Documentation/NuttX.html
index ab7b55fe0..c048fe472 100644
--- a/nuttx/Documentation/NuttX.html
+++ b/nuttx/Documentation/NuttX.html
@@ -111,7 +111,7 @@ is available that be used to build a NuttX-compatible arm-elf toolchain.</blockq
 <p><b>C5471 (Arm7)</b>
   The build for this ARM7 target that includes most of the OS features and
   a broad range of OS tests.  The size of this executable as given by the
-  Linux <tt>size</tt> command is:
+  Linux <tt>size</tt> command is (3/9/07):
 </p>
 <pre>
    text    data     bss     dec     hex filename
diff --git a/nuttx/arch/pjrc-8051/defconfig b/nuttx/arch/pjrc-8051/defconfig
index 54bab70ea..8e122c065 100644
--- a/nuttx/arch/pjrc-8051/defconfig
+++ b/nuttx/arch/pjrc-8051/defconfig
@@ -33,16 +33,47 @@
 #
 ############################################################
 #
-# architecture selection
+# Architecture selection
 #
 # CONFIG_ARCH - identifies the arch subdirectory
-# CONFIG_ARCH_name - for use in C code
-# CONFIG_PJRC_LEDS - Use LEDs to show state. Unique to 8051.
+# CONFIG_ARCH_8051 - Set if processor is 8051 family
+# CONFIG_ARCH_8052 = Set if processor is 8052 family
 #
 CONFIG_ARCH=pjrc-8051
+CONFIG_ARCH_8051=n
 CONFIG_ARCH_8052=y
+
+#
+# Architecture-specific settings.  These may mean nothing to
+# other architectures.
+#
+# CONFIG-ARCH_PJRC - Set if using the PJRC 87C52 board
+# CONFIG_ARCH_LEDS - Use LEDs to show state. Unique to 8051.
+# CONFIG_8052_TIMER2 - Use timer2 for the 100Hz system timer.
+#   (default is timer0 at 112.5Hz).
+#
+# These features are only supported when CONFIG_ARCH_BRINGUP
+# is set:
+#
+# CONFIG_ARCH_BRINGUP - Enables some bringup features
+# CONFIG_FRAME_DUMP - Enable stack/frame dumping logic
+# CONFIG_FRAME_DUMP_SHORT - Terse frame dump output
+# CONFIG_SUPPRESS_INTERRUPTS - Do not enable interrupts
+# CONFIG_SWITCH_FRAME_DUMP - Dump frames from normal switches
+# CONFIG_INTERRUPT_FRAME_DUMP - Dump frames from interrupt switches
+# CONFIG_LED_DEBUG - Enable debug output from LED logic
+#
 CONFIG_ARCH_PJRC=y
-CONFIG_8051_LEDS=y
+CONFIG_ARCH_LEDS=y
+CONFIG_8052_TIMER2=y
+
+CONFIG_ARCH_BRINGUP=y
+CONFIG_FRAME_DUMP=y
+CONFIG_FRAME_DUMP_SHORT=n
+CONFIG_SUPPRESS_INTERRUPTS=y
+CONFIG_SWITCH_FRAME_DUMP=y
+CONFIG_INTERRUPT_FRAME_DUMP=n
+CONFIG_LED_DEBUG=n
 
 #
 # General OS setup
diff --git a/nuttx/arch/pjrc-8051/src/pjrc.h b/nuttx/arch/pjrc-8051/src/pjrc.h
index fd875d388..0934c78be 100644
--- a/nuttx/arch/pjrc-8051/src/pjrc.h
+++ b/nuttx/arch/pjrc-8051/src/pjrc.h
@@ -183,8 +183,7 @@ sfr at 0xc9 T2MOD ;
  * Timer 0 provides only a 8-bit auto-reload mode.
  */
 
-#define CONFIG_80C52_TIMER2 1
-#ifdef CONFIG_80C52_TIMER2
+#ifdef CONFIG_8052_TIMER2
 
 /* To use timer 2 as the 100Hz system timer, we need to calculate a 16-bit
  * reload value that results in 100Hz overflow interrupts.  That value
@@ -207,8 +206,6 @@ sfr at 0xc9 T2MOD ;
  * second.
  */
 
-# warning "No support for timer 0 as the system timer"
-
 #endif
 
 /**************************************************************************
diff --git a/nuttx/arch/pjrc-8051/src/up_assert.c b/nuttx/arch/pjrc-8051/src/up_assert.c
index 6fc77bec9..01bec26ca 100644
--- a/nuttx/arch/pjrc-8051/src/up_assert.c
+++ b/nuttx/arch/pjrc-8051/src/up_assert.c
@@ -73,7 +73,7 @@ static void _up_assert(int errorcode) /* __attribute__ ((noreturn)) */
        (void)irqsave();
         for(;;)
           {
-#ifdef CONFIG_8051_LEDS
+#ifdef CONFIG_ARCH_LEDS
             up_ledon(LED_PANIC);
             up_delay(250);
             up_ledoff(LED_PANIC);
diff --git a/nuttx/arch/pjrc-8051/src/up_debug.c b/nuttx/arch/pjrc-8051/src/up_debug.c
index 3ca2acae7..9b52250e2 100644
--- a/nuttx/arch/pjrc-8051/src/up_debug.c
+++ b/nuttx/arch/pjrc-8051/src/up_debug.c
@@ -58,17 +58,8 @@
  * Private Functions
  ************************************************************/
 
-#ifdef CONFIG_FRAME_DUMP
-static void _up_puthex(ubyte hex) __naked
-{
-  hex; /* To avoid unreferenced argument warning */
-  _asm
-        mov     a, dpl
-        ljmp    PM2_ENTRY_PHEX
-  _endasm;
-}
-
-static void _up_putspace(void) __naked
+#if defined(CONFIG_FRAME_DUMP) && defined(CONFIG_ARCH_BRINGUP)
+static void up_putspace(void) __naked
 {
   _asm
         mov     a, #0x20
@@ -84,46 +75,69 @@ static void _up_putcolon(void) __naked
   _endasm;
 }
 
-static void _up_putnl(void) __naked
+static void _up_dump16(__code char *ptr, ubyte msb, ubyte lsb)
+{
+  up_puts(ptr);
+  up_puthex(msb);
+  up_puthex(lsb);
+  up_putnl();
+}
+
+static void _up_dump8(__code char *ptr, ubyte b)
+{
+  up_puts(ptr);
+  up_puthex(b);
+  up_putnl();
+}
+#endif
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: up_puthex, up_puthex16, up_putnl, up_puts
+ ************************************************************/
+
+#if defined(CONFIG_ARCH_BRINGUP)
+void up_puthex(ubyte hex) __naked
 {
+  hex; /* To avoid unreferenced argument warning */
   _asm
-	ljmp	PM2_ENTRY_NEWLINE
+        mov     a, dpl
+        ljmp    PM2_ENTRY_PHEX
   _endasm;
 }
 
-static void _up_puts(__code char *ptr)
+void up_puthex16(int hex) __naked
 {
-  for (; *ptr; ptr++)
-    {
-       up_putc(*ptr);
-    }
+  hex; /* To avoid unreferenced argument warning */
+  _asm
+        ljmp    PM2_ENTRY_PHEX16
+  _endasm;
 }
 
-static void _up_dump16(__code char *ptr, ubyte msb, ubyte lsb)
+void up_putnl(void) __naked
 {
-  _up_puts(ptr);
-  _up_puthex(msb);
-  _up_puthex(lsb);
-  _up_putnl();
+  _asm
+	ljmp	PM2_ENTRY_NEWLINE
+  _endasm;
 }
 
-static void _up_dump8(__code char *ptr, ubyte b)
+void up_puts(__code char *ptr)
 {
-  _up_puts(ptr);
-  _up_puthex(b);
-  _up_putnl();
+  for (; *ptr; ptr++)
+    {
+       up_putc(*ptr);
+    }
 }
 #endif
 
 /************************************************************
- * Public Functions
- ************************************************************/
-
-/************************************************************
  * Name: up_dumpstack
  ************************************************************/
 
-#ifdef CONFIG_FRAME_DUMP
+#if defined(CONFIG_FRAME_DUMP) && defined(CONFIG_ARCH_BRINGUP)
 void up_dumpstack(void)
 {
   NEAR ubyte *start = (NEAR ubyte *)(STACK_BASE & 0xf0);
@@ -132,25 +146,25 @@ void up_dumpstack(void)
 
   while (start < end)
     {
-      _up_puthex((ubyte)start);
+      up_puthex((ubyte)start);
       _up_putcolon();
 
       for (i = 0; i < 8; i++)
         {
-          _up_putspace();
+          up_putspace();
           if (start < (NEAR ubyte *)(STACK_BASE) ||
               start > end)
             {
-              _up_putspace();
-              _up_putspace();
+              up_putspace();
+              up_putspace();
             }
           else
             {
-              _up_puthex(*start);
+              up_puthex(*start);
             }
           start++;
         }
-      _up_putnl();
+      up_putnl();
     }
 }
 #endif
@@ -159,7 +173,7 @@ void up_dumpstack(void)
  * Name: up_dumpframe
  ************************************************************/
 
-#ifdef CONFIG_FRAME_DUMP
+#if defined(CONFIG_FRAME_DUMP) && defined(CONFIG_ARCH_BRINGUP)
 void up_dumpframe(FAR struct xcptcontext *context)
 {
 #ifdef CONFIG_FRAME_DUMP_SHORT
@@ -180,33 +194,33 @@ void up_dumpframe(FAR struct xcptcontext *context)
 
   for (i = 0; i < context->nbytes; i += 8)
     {
-      _up_puthex(i);
+      up_puthex(i);
       _up_putcolon();
 
       for (j = 0; j < 8; j++)
         {
           k = i + j;
-          _up_putspace();
+          up_putspace();
           if (k >= context->nbytes)
             {
-              _up_putspace();
-              _up_putspace();
+              up_putspace();
+              up_putspace();
             }
           else
             {
-              _up_puthex(context->stack[k]);
+              up_puthex(context->stack[k]);
             }
         }
-      _up_putnl();
+      up_putnl();
     }
 
-  _up_puts("  REGS:");
+  up_puts("  REGS:");
   for (i = 0; i < REGS_SIZE; i++)
     {
-      _up_putspace();
-      _up_puthex(context->regs[i]);
+      up_putspace();
+      up_puthex(context->regs[i]);
     }
-   _up_putnl();
+   up_putnl();
 #endif
 }
 #endif
diff --git a/nuttx/arch/pjrc-8051/src/up_head.S b/nuttx/arch/pjrc-8051/src/up_head.S
index 1981e5dd8..44f8038c9 100644
--- a/nuttx/arch/pjrc-8051/src/up_head.S
+++ b/nuttx/arch/pjrc-8051/src/up_head.S
@@ -51,6 +51,12 @@
 	.area REG_BANK_0	(REL,OVR,DATA)
 	.ds 8
 
+#ifndef CONFIG_8052_TIMER2
+	.area	XSEG
+_g_timer0tick:
+	.ds 1
+#endif
+
 /************************************************************
  * Public Data
  ************************************************************/
@@ -93,9 +99,12 @@
 
 	.org	PM2_VECTOR_TIMER0
 	push	acc
+#ifdef CONFIG_8052_TIMER2
 	mov	a, #TIMER0_IRQ
 	ljmp	_up_interrupt
-
+#else
+	ljmp	_up_timer0
+#endif
 	.org	PM2_VECTOR_EXTINT1
 	push	acc
 	mov	a, #EXT_INT1_IRQ
@@ -127,13 +136,77 @@
 start:
 	mov	sp, #(STACK_BASE-1)
 
-#ifdef CONFIG_8051_LEDS
+#ifdef CONFIG_ARCH_LEDS
 	lcall	_up_ledinit
 #endif
 
 	ljmp	_os_start
 
 /************************************************************
+ * Name: up_timer0
+ *
+ * Description:
+ *   Timer 0, mode 0 can be used as a system timer.  In that
+ *   mode, the 1.8432 MHz clock is divided by 32.  A single
+ *   8-bit value is incremented at 57600 Hz, which results
+ *   in 225 Timer 0 overflow interrupts per second.
+ *
+ *   The Timer0 interrupt vectors to this point which then
+ *   does a software divide by 2 to get a system timer of
+ *   112.5Hz.
+ *
+ *   On Entry:
+ *
+ *   (1) acc on the stack and
+ *   (2) the IRQ number(TIMER0_IRQ) in the accumulator
+ *
+ ************************************************************/
+
+#ifndef CONFIG_8052_TIMER2
+_up_timer0:
+	ar2 = 0x02
+	ar3 = 0x03
+	ar4 = 0x04
+	ar5 = 0x05
+	ar6 = 0x06
+	ar7 = 0x07
+	ar0 = 0x00
+	ar1 = 0x01
+
+	/* ACC already on the stack; push IE.  Then disable interrupts */
+
+	push	ie
+	clr	ea
+
+	/* Save the remaining registers with interrupts disabled 
+	 *
+	 * a, ie, and dptr go on the stack.
+	 */
+
+	push	dpl
+	push	dph
+
+	/* Increment the tick counter */
+
+	mov	dptr, #_g_timer0tick
+        movx    a, @dptr
+	inc	a
+	movx	@dptr, a
+
+	/* If bit 0 is '0', then just return from the interrupt */
+
+	anl	a, #0x01
+	jnz	00101$
+	ljmp	_up_timer0exit
+
+	/* If bit 0 is '1', then process the interrupt */
+
+00101$:
+	mov	a, #TIMER0_IRQ
+	sjmp	_up_timer0join
+#endif
+
+/************************************************************
  * Name: up_interrupt
  *
  * Description:
@@ -167,6 +240,7 @@ _up_interrupt:
 	push	dpl
 	push	dph
 
+_up_timer0join:
 	/* Other registers go into the IRQ register save area */
 
 	push	acc
@@ -175,7 +249,7 @@ _up_interrupt:
 
 	/* Show interrupt status on the LEDs */
 
-#ifdef CONFIG_8051_LEDS
+#ifdef CONFIG_ARCH_LEDS
 	mov	dpl, #LED_INIRQ
 	lcall	_up_ledon
 #endif
@@ -343,12 +417,12 @@ _up_interrupt:
 	push	dpl
 	push	dph
 	lcall	_up_dumpstack
-	pop	dpl
 	pop	dph
+	pop	dpl
 #endif
 	/* Get the pointer to the register save area */
 
-	mov	a, #FRAME_SIZE
+	mov	a, #STACK_SIZE
 	add	a, dpl
 	mov	dpl, a
 	clr	a
@@ -365,18 +439,19 @@ _up_interrupt:
 	 * (context switch).
 	 */
 
-#ifdef CONFIG_8051_LEDS
+#ifdef CONFIG_ARCH_LEDS
 	push	dpl
 	push	dph
 	mov	dpl, #LED_INIRQ
 	lcall	_up_ledoff
-	pop	dpl
 	pop	dph
+	pop	dpl
 #endif
 	/* Restore registers from the register save area */
 
 	lcall	_up_restoreregisters
 
+_up_timer0exit:
 	/* Restore registers from the stack and return */
 
 	pop	dph
diff --git a/nuttx/arch/pjrc-8051/src/up_idle.c b/nuttx/arch/pjrc-8051/src/up_idle.c
index c413c3f41..7c9ebc040 100644
--- a/nuttx/arch/pjrc-8051/src/up_idle.c
+++ b/nuttx/arch/pjrc-8051/src/up_idle.c
@@ -50,7 +50,7 @@
  * Private Data
  ************************************************************/
 
-#if defined(CONFIG_8051_LEDS) && defined(CONFIG_8051_BRINGUP)
+#if defined(CONFIG_ARCH_LEDS) && defined(CONFIG_ARCH_BRINGUP)
 static ubyte g_ledtoggle = 0;
 #endif
 
@@ -79,7 +79,7 @@ static ubyte g_ledtoggle = 0;
 
 void up_idle(void)
 {
-#if defined(CONFIG_8051_LEDS) && defined(CONFIG_8051_BRINGUP)
+#if defined(CONFIG_ARCH_LEDS) && defined(CONFIG_ARCH_BRINGUP)
   g_ledtoggle++;
   if (g_ledtoggle == 0x80)
     {
diff --git a/nuttx/arch/pjrc-8051/src/up_internal.h b/nuttx/arch/pjrc-8051/src/up_internal.h
index 634803054..80900ca56 100644
--- a/nuttx/arch/pjrc-8051/src/up_internal.h
+++ b/nuttx/arch/pjrc-8051/src/up_internal.h
@@ -50,16 +50,6 @@
  * Public Definitions
  **************************************************************************/
 
-/* Bring-up debug configurations */
-
-#define CONFIG_8051_BRINGUP         1   /* Enables some bringup features */
-#define CONFIG_FRAME_DUMP           1   /* Enable stack/frame dumping logic */
-#undef  CONFIG_FRAME_DUMP_SHORT         /* Terse frame dump output */
-#define CONFIG_SUPPRESS_INTERRUPTS  1   /* Do not enable interrupts */
-#define CONFIG_SWITCH_FRAME_DUMP    1   /* Dump frames from normal switches */
-#undef  CONFIG_INTERRUPT_FRAME_DUMP     /* Dump frames from interrupt switches */
-#define CONFIG_LED_DEBUG            1   /* Enabled debug output from LED logic */
-
 /**************************************************************************
  * Public Types
  **************************************************************************/
@@ -124,9 +114,16 @@ extern void  up_saveregisters(FAR ubyte *regs) _naked;
 extern void  up_saveirqcontext(FAR struct xcptcontext *context);
 extern void  up_timerinit(void);
 
-/* Defined in up_assert.c */
+/* Defined in up_debug.c */
+
+#if defined(CONFIG_ARCH_BRINGUP)
+extern void up_puthex(ubyte hex) __naked;
+extern void up_puthex16(int hex) __naked;
+extern void up_putnl(void) __naked;
+extern void up_puts(__code char *ptr);
+#endif
 
-#ifdef CONFIG_FRAME_DUMP
+#if defined(CONFIG_FRAME_DUMP) && defined(CONFIG_ARCH_BRINGUP)
 extern void up_dumpstack(void);
 extern void up_dumpframe(FAR struct xcptcontext *context);
 #else
@@ -136,7 +133,7 @@ extern void up_dumpframe(FAR struct xcptcontext *context);
 
 /* Defined in up_leds.c */
 
-#ifdef CONFIG_8051_LEDS
+#ifdef CONFIG_ARCH_LEDS
 extern void up_ledinit(void);
 extern void up_ledon(ubyte led);
 extern void up_ledoff(ubyte led);
diff --git a/nuttx/arch/pjrc-8051/src/up_irq.c b/nuttx/arch/pjrc-8051/src/up_irq.c
index bf76b25a8..a23e4c17b 100644
--- a/nuttx/arch/pjrc-8051/src/up_irq.c
+++ b/nuttx/arch/pjrc-8051/src/up_irq.c
@@ -71,6 +71,10 @@ extern int g_nints;
 
 void up_irqinitialize(void)
 {
+  /* Set interrupt priorities (all low) */
+
+  IP = 0;
+
 #ifdef CONFIG_SUPPRESS_INTERRUPTS
   /* Disable all interrupts */
 
diff --git a/nuttx/arch/pjrc-8051/src/up_leds.c b/nuttx/arch/pjrc-8051/src/up_leds.c
index 41d8ac8fa..c7730ac3e 100644
--- a/nuttx/arch/pjrc-8051/src/up_leds.c
+++ b/nuttx/arch/pjrc-8051/src/up_leds.c
@@ -57,7 +57,7 @@ static ubyte g_ledstate;
  * Private Functions
  ************************************************************/
 
-#if defined(CONFIG_LED_DEBUG) && defined(CONFIG_8051_LEDS)
+#if defined(CONFIG_LED_DEBUG) && defined(CONFIG_ARCH_LEDS)
 static void _up_puthex(ubyte hex) __naked
 {
   hex; /* To avoid unreferenced argument warning */
@@ -122,7 +122,7 @@ static void _up_putnl(void) __naked
  * Name: up_ledinit
  ************************************************************/
 
-#ifdef CONFIG_8051_LEDS
+#ifdef CONFIG_ARCH_LEDS
 void up_ledinit(void)
 {
   /* Set all ports as outputs */
@@ -143,6 +143,10 @@ void up_ledinit(void)
 
 void up_ledon(ubyte led)
 {
+  /* This may be called from an interrupt handler */
+
+  irqstate_t flags = irqsave();
+
 #ifdef RESET_KLUDGE_NEEDED
   /* I don't understand why this happens yet, but sometimes
    * it is necessary to reconfigure port E.
@@ -164,6 +168,7 @@ void up_ledon(ubyte led)
     }
 
   _up_showledon();
+  irqrestore(flags);
 }
 
 /************************************************************
@@ -172,6 +177,10 @@ void up_ledon(ubyte led)
 
 void up_ledoff(ubyte led)
 {
+  /* This may be called from an interrupt handler */
+
+  irqstate_t flags = irqsave();
+
 #ifdef RESET_KLUDGE_NEEDED
   /* I don't understand why this happens yet, but sometimes
    * it is necessary to reconfigure port E.
@@ -193,5 +202,6 @@ void up_ledoff(ubyte led)
     }
 
   _up_showledoff();
+  irqrestore(flags);
 }
-#endif /* CONFIG_8051_LEDS */
+#endif /* CONFIG_ARCH_LEDS */
diff --git a/nuttx/arch/pjrc-8051/src/up_restorecontext.c b/nuttx/arch/pjrc-8051/src/up_restorecontext.c
index bdb2fea24..fa7c8c2d0 100644
--- a/nuttx/arch/pjrc-8051/src/up_restorecontext.c
+++ b/nuttx/arch/pjrc-8051/src/up_restorecontext.c
@@ -37,6 +37,7 @@
  * Included Files
  **************************************************************************/
 
+#include <nuttx/config.h>
 #include <nuttx/irq.h>
 #include "up_internal.h"
 
@@ -260,7 +261,7 @@ void up_restorecontext(FAR struct xcptcontext *context) __naked
 #endif
 	/* Get the pointer to the register save area */
 
-	mov	a, #FRAME_SIZE
+	mov	a, #STACK_SIZE
 	add	a, dpl
 	mov	dpl, a
 	clr	a
diff --git a/nuttx/arch/pjrc-8051/src/up_savecontext.c b/nuttx/arch/pjrc-8051/src/up_savecontext.c
index 346f9271d..83310534c 100644
--- a/nuttx/arch/pjrc-8051/src/up_savecontext.c
+++ b/nuttx/arch/pjrc-8051/src/up_savecontext.c
@@ -37,6 +37,7 @@
  * Included Files
  **************************************************************************/
 
+#include <nuttx/config.h>
 #include <sys/types.h>
 #include <nuttx/irq.h>
 #include "up_internal.h"
diff --git a/nuttx/arch/pjrc-8051/src/up_timerisr.c b/nuttx/arch/pjrc-8051/src/up_timerisr.c
index 5580b5bb5..8f139d89a 100644
--- a/nuttx/arch/pjrc-8051/src/up_timerisr.c
+++ b/nuttx/arch/pjrc-8051/src/up_timerisr.c
@@ -89,10 +89,10 @@ int up_timerisr(int irq, FAR ubyte *frame)
 
 void up_timerinit(void)
 {
-#ifdef CONFIG_80C52_TIMER2
+#ifdef CONFIG_8052_TIMER2
   up_disable_irq(TIMER2_IRQ);
 
-  /* Set up timer 2 -- See up_internal.h for details */
+  /* Set up timer 2 -- See pjrc.h for details */
 
   T2MOD  = 0;
 
@@ -108,7 +108,7 @@ void up_timerinit(void)
 
   /* Configure for interrupts */
 
-  T2CON  = 0x40;
+  T2CON  = 0x04;
 
   /* Attach and enable the timer interrupt */
 
@@ -116,6 +116,29 @@ void up_timerinit(void)
   up_enable_irq(TIMER2_IRQ);
 
 #else
+  /* Timer 0, mode 0 can be used as a system timer.  In that mode, the
+   * 1.8432 MHz clock is divided by 32.  A single 8-bit value is incremented
+   * at 57600 Hz, which results in 225 Timer 0 overflow interrupts per
+   * second.
+   */
+
+  up_disable_irq(TIMER0_IRQ);
+
+  /* Initialize timer 0 */
+
+  TR0   = 0;     /* Make sure timer 0 is stopped */
+  TF0   = 0;     /* Clear the overflow flag */
+  TMOD &= 0xF0;  /* Set to mode 0 (without changing timer1) */
+  TL0   = 0;     /* Clear timer 0 value */
+  TH0   = 0;
+
+  /* Attach and enable the timer interrupt */
+
+  irq_attach(TIMER0_IRQ, (xcpt_t)up_timerisr);
+
+  TR0 = 1;       /* Start the timer */
+  up_enable_irq(TIMER0_IRQ);
+
 # warning "No support for timer 0 as the system timer"
 #endif
 }
diff --git a/nuttx/sched/os_internal.h b/nuttx/sched/os_internal.h
index ca2222ad6..0fa7172b5 100644
--- a/nuttx/sched/os_internal.h
+++ b/nuttx/sched/os_internal.h
@@ -243,7 +243,7 @@ extern void    task_start(void);
 extern STATUS  task_schedsetup(FAR _TCB *tcb, int priority,
                                start_t start, main_t main);
 extern STATUS  task_argsetup(FAR _TCB *tcb, const char *name,
-                             boolean pthread, char *argv[]);
+                             char *argv[]);
 
 extern boolean sched_addreadytorun(FAR _TCB *rtrtcb);
 extern boolean sched_removereadytorun(FAR _TCB *rtrtcb);
diff --git a/nuttx/sched/pthread_create.c b/nuttx/sched/pthread_create.c
index 33fdcf00f..4346a6f65 100644
--- a/nuttx/sched/pthread_create.c
+++ b/nuttx/sched/pthread_create.c
@@ -75,11 +75,74 @@ FAR pthread_attr_t g_default_pthread_attr =
  * Private Variables
  ************************************************************/
 
+/* This is the name for name-less pthreads */
+
+static const char g_pthreadname[] = "<pthread>";
+
 /************************************************************
  * Private Functions
  ************************************************************/
 
 /************************************************************
+ * Name: pthread_argsetup
+ *
+ * Description:
+ *   This functions sets up parameters in the Task Control
+ *   Block (TCB) in preparation for starting a new thread.
+ *
+ *   pthread_argsetup() is called from task_init() and task_start()
+ *   to create a new task (with arguments cloned via strdup)
+ *   or pthread_create() which has one argument passed by
+ *   value (distinguished by the pthread boolean argument).
+ *
+ * Input Parameters:
+ *   tcb        - Address of the new task's TCB
+ *   name       - Name of the new task (not used)
+ *   argv       - A pointer to an array of input parameters.
+ *                Up to CONFIG_MAX_TASK_ARG parameters may be
+ *                provided. If fewer than CONFIG_MAX_TASK_ARG
+ *                parameters are passed, the list should be
+ *                terminated with a NULL argv[] value.
+ *                If no parameters are required, argv may be NULL.
+ *
+ * Return Value:
+ *  OK
+ *
+ ************************************************************/
+
+static void pthread_argsetup(FAR _TCB *tcb, pthread_addr_t arg)
+{
+  int i;
+
+#if CONFIG_TASK_NAME_SIZE > 0
+  /* Copy the pthread name into the TCB */
+
+  strncpy(tcb->name, g_pthreadname, CONFIG_TASK_NAME_SIZE);
+
+  /* Save the name as the first argument in the TCB */
+
+  tcb->argv[0] = tcb->name;
+#else
+  /* Save the name as the first argument in the TCB */
+
+  tcb->argv[0] = (char *)g_pthreadname;
+#endif /* CONFIG_TASK_NAME_SIZE */
+
+  /* For pthreads, args are strictly pass-by-value; that actual
+   * type wrapped by pthread_addr_t is unknown.
+   */
+
+  tcb->argv[1]  = (char*)arg;
+
+  /* Nullify the remaining, unused argument storage */
+
+  for (i = 2; i < CONFIG_MAX_TASK_ARGS+1; i++)
+    {
+      tcb->argv[i] = NULL;
+    }
+}
+
+/************************************************************
  * Function:  pthread_addjoininfo
  *
  * Description:
@@ -178,7 +241,6 @@ int pthread_create(pthread_t *thread, pthread_attr_t *attr,
   FAR _TCB *ptcb;
   FAR join_t *pjoin;
   STATUS status;
-  char *argv[2];
   int priority;
 #if CONFIG_RR_INTERVAL > 0
   int policy;
@@ -280,13 +342,15 @@ int pthread_create(pthread_t *thread, pthread_attr_t *attr,
       return ERROR;
     }
 
+  /* Mark this task as a pthread */
+
+  ptcb->flags |= TCB_FLAG_PTHREAD;
+
   /* Configure the TCB for a pthread receiving on parameter
    * passed by value
    */
 
-  argv[0] = (char *)arg;
-  argv[1] = NULL;
-  (void)task_argsetup(ptcb, NULL, TRUE, argv);
+  (void)pthread_argsetup(ptcb, arg);
 
   /* Attach the join info to the TCB. */
 
diff --git a/nuttx/sched/task_create.c b/nuttx/sched/task_create.c
index c3d1b453b..04313c499 100644
--- a/nuttx/sched/task_create.c
+++ b/nuttx/sched/task_create.c
@@ -159,7 +159,7 @@ int task_create(const char *name, int priority,
 
   /* Setup to pass parameters to the new task */
 
-  (void)task_argsetup(tcb, name, FALSE, argv);
+  (void)task_argsetup(tcb, name, argv);
 
   /* Get the assigned pid before we start the task */
 
diff --git a/nuttx/sched/task_init.c b/nuttx/sched/task_init.c
index 92fd53fb2..f1dc42292 100644
--- a/nuttx/sched/task_init.c
+++ b/nuttx/sched/task_init.c
@@ -127,7 +127,7 @@ STATUS task_init(FAR _TCB *tcb, const char *name, int priority,
     {
       /* Setup to pass parameters to the new task */
 
-      (void)task_argsetup(tcb, name, FALSE, argv);
+      (void)task_argsetup(tcb, name, argv);
     }
   return ret;
  }
diff --git a/nuttx/sched/task_setup.c b/nuttx/sched/task_setup.c
index 744f5fbf4..fbce5fcee 100644
--- a/nuttx/sched/task_setup.c
+++ b/nuttx/sched/task_setup.c
@@ -64,13 +64,13 @@
 
 /* This is the name for un-named tasks */
 
-static const char g_noname[] = "no name";
+static const char g_noname[] = "<noname>";
 
 /************************************************************
  * Private Function Prototypes
  ************************************************************/
 
-static STATUS   task_assignpid(FAR _TCB* tcb);
+static STATUS task_assignpid(FAR _TCB* tcb);
 
 /************************************************************
  * Private Functions
@@ -216,15 +216,13 @@ STATUS task_schedsetup(FAR _TCB *tcb, int priority,
  *   This functions sets up parameters in the Task Control
  *   Block (TCB) in preparation for starting a new thread.
  *
- *   task_argsetup() is called from task_init() and task_start()
- *   to create a new task (with arguments cloned via strdup)
- *   or pthread_create() which has one argument passed by
- *   value (distinguished by the pthread boolean argument).
+ *   task_argsetup() is called only from task_init() and
+ *   task_start() to create a new task.  Argumens are
+ *   cloned via strdup.
  *
  * Input Parameters:
  *   tcb        - Address of the new task's TCB
  *   name       - Name of the new task (not used)
- *   pthread    - TRUE is the task emulates pthread behavior
  *   argv       - A pointer to an array of input parameters.
  *                Up to CONFIG_MAX_TASK_ARG parameters may be
  *                provided. If fewer than CONFIG_MAX_TASK_ARG
@@ -237,69 +235,48 @@ STATUS task_schedsetup(FAR _TCB *tcb, int priority,
  *
  ************************************************************/
 
-STATUS task_argsetup(FAR _TCB *tcb, const char *name,
-                     boolean pthread, char *argv[])
+STATUS task_argsetup(FAR _TCB *tcb, const char *name, char *argv[])
 {
   int i;
 
 #if CONFIG_TASK_NAME_SIZE > 0
-  /* Give a name to the unnamed threads */
+  /* Give a name to the unnamed tasks */
 
   if (!name)
     {
       name = (char *)g_noname;
     }
 
-  /* copy the name into the TCB */
+  /* Copy the name into the TCB */
 
   strncpy(tcb->name, name, CONFIG_TASK_NAME_SIZE);
-#endif /* CONFIG_TASK_NAME_SIZE */
 
-  /* Save the arguments in the TCB */
+  /* Save the name as the first argument */
 
-#if CONFIG_TASK_NAME_SIZE > 0
   tcb->argv[0] = tcb->name;
 #else
+  /* Save the name as the first argument */
+
   tcb->argv[0] = (char *)g_noname;
-#endif
+#endif /* CONFIG_TASK_NAME_SIZE */
 
-  /* For pthreads, args are strictly pass-by-value; the char*
-   * arguments wrap some unknown value cast to char*.  However,
-   * for tasks, the life of the argument must be as long as
+  /* For tasks, the life of the argument must be as long as
    * the life of the task and the arguments must be strings.
    * So for tasks, we have to to dup the strings.
+   *
+   * The first NULL argument terminates the list of 
+   * arguments.  The argv pointer may be NULL if no
+   * parameters are passed.
    */
 
-  if (!pthread)
+  i = 1;
+  if (argv)
     {
-      /* The first NULL argument terminates the list of 
-       * arguments.  The argv pointer may be NULL if no
-       * parameters are passed.
-       */
-
-      i = 1;
-      if (argv)
+      for (; i < CONFIG_MAX_TASK_ARGS+1 && argv[i-1]; i++)
         {
-          for (; i < CONFIG_MAX_TASK_ARGS+1 && argv[i-1]; i++)
-            {
-              tcb->argv[i] = strdup(argv[i-1]);
-            }
+          tcb->argv[i] = strdup(argv[i-1]);
         }
     }
-  else
-    {
-      /* Mark this task as a pthread */
-
-      tcb->flags   |= TCB_FLAG_PTHREAD;
-
-      /* And just copy the argument. For pthreads, there
-       * is really only a single argument, argv[0].  It is
-       * copied as a value -- NOT duplicated.
-       */
-
-      i = 2;
-      tcb->argv[1]  = argv[0];
-    }
 
   /* Nullify any unused argument storage */