/*******************************************************************************
* FILENAME
*   FlashBlink.c
*
* DESCRIPTION
*   DSP Program intended as a demo for
*   DSK 6211 Flash Memory Downloader, called
*   FlashBurn.
*   This was adapted from the blink example
*   which is shipped with the DSK 6211 package.
*
*******************************************************************************/
#include <c6x.h>
#include <c6211dsk.h>
 
/*******************************************************************************
* Function prototypes
*******************************************************************************/
void led_blink(int count, int ms_period);
void delay_msec(short msec);
int  timer0_read();
void timer0_start();
void timer0_init();

/*******************************************************************************
* FUNCTION : main
*
* ARGUMENTS :
*   VOID
*
* DESCRIPTION :
*   The code is just a blinker test function
*
*******************************************************************************/
int main()
{
  /* DSP initialization                                                       */
  CSR=0x100;                           /* Disable all interrupts              */
  IER=1;                               /* Disable all interrupts except NMI   */
  ICR=0xffff;                          /* Clear all pending interrupts        */

/*************************************************************************
* Standard 6211/6711 DSK includes 2 MT48LC1M16A1-7 devices = 4MB SDRAM   *
* For these devices use the following parameter:                         *
*   EMIF_SDCTRL=0x07126000                                               *
* If MT48LC1M16A1-10 devices are installed use the following parameter:  *
*   EMIF_SDCTRL=0x07227000                                               *
* /|\ 16Mb parts = 4MB SDRAM /|\   *-------------------------------------*
*----------------------------------*   \|/ 64Mb parts = 16MB SDRAM \|/   *
* If MT48LC4M16A2-10 devices are installed use the following parameter:  *
*   EMIF_SDCTRL=0x57227000                                               *
*************************************************************************/

  *(unsigned volatile int *)EMIF_GCR = 0x3300;    /* EMIF global control      */
  *(unsigned volatile int *)EMIF_CE1 = CE1_32;    /* EMIF CE1 control, 32bit  */
  *(unsigned volatile int *)EMIF_SDCTRL = 0x07126000; /* EMIF SDRAM control   */ 
  *(unsigned volatile int *)EMIF_CE0 = 0x30;      /* EMIF CE0 control         */
  *(unsigned volatile int *)EMIF_SDRP = 0x61a;    /* EMIF SDRM refresh period */
  *(unsigned volatile int *)EMIF_SDEXT= 0x54529;  /* EMIF SDRM extension      */

  /*****************************************************************************
   * Start state
   ****************************************************************************/
  delay_msec(50);
  *(unsigned volatile int *)IO_PORT = 0x07000000; /* Turn off all user LEDs*/
  delay_msec(500);

  *(unsigned volatile int *)IO_PORT = 0x0e000000; /* Display 1 on LEDs */
  delay_msec(500);

  *(unsigned volatile int *)IO_PORT = 0x0D000000; /* Display 2 on LEDs */
  delay_msec(500);

  *(unsigned volatile int *)IO_PORT = 0x0C000000; /* Display 3 on LEDs */ 
  delay_msec(500);
 
  *(unsigned volatile int *)IO_PORT = 0x0B000000; /* Display 4 on LEDs */ 
  delay_msec(500);

  *(unsigned volatile int *)IO_PORT = 0x0A000000; /* Display 5 on LEDs */ 
  delay_msec(500);

  *(unsigned volatile int *)IO_PORT = 0x09000000; /* Display 6 on LEDs */  
  delay_msec(500);

/*
 ****************************************************************************
 * Flash LEDS forever, 3 blinks, then 1/2 sec. off.
 * THis makes it a different pattern from the
 * blink example shipped with the DSK.
 ****************************************************************************
 */
  for (;;)
  {
    led_blink(3, 200);
  	delay_msec(500);
  }
}

/*******************************************************************************
* FUNCTION : led_blink
*
* ARGUMENTS :
*   INT count             <-- Number of times to blink the LEDs
*   INT ms_period         <-- Time the LED(s) is(are) active (illuminated)
*   
* DESCRIPTION :
*   Toggles the user LEDs for a given count and period (in milliseconds).
*   
* OUTPUTS :
*   VOID
*   
*******************************************************************************/
void led_blink(int count, int ms_period)
{
  int i;
  
  for (i=0;i<count;i++)
  {
    *(unsigned volatile int *)IO_PORT = 0x0;        /* Turn on all user LEDs */
    delay_msec(ms_period/2);
    *(unsigned volatile int *)IO_PORT = 0x07000000; /* Turn off all user LEDs*/
    delay_msec(ms_period/2);
  }
  *(unsigned volatile int *)IO_PORT = 0x07000000;   /* Turn off all user LEDs */
}

/*******************************************************************************
* FUNCTION : delay_msec
*
* ARGUMENTS :
*   SHORT msec            <-- Period to delay in milliseconds
*
* DESCRIPTION :
*
*
* OUTPUTS :
*   VOID
*
*******************************************************************************/
void delay_msec(short msec)
{
  /* Assume 150 MHz CPU, timer peirod = 4/150 MHz */
  int timer_limit = (msec*9375)<<2;
  int time_start;

  timer0_start();
  time_start = timer0_read();
  while ((timer0_read()-time_start) < timer_limit);
}
 
/*******************************************************************************
* FUNCTION : timer0_read
*
* ARGUMENTS :
*   VOID
*
* DESCRIPTION :
*   Read and return the count in timer 0.
*
* OUTPUTS :
*   INT                   <-- Returns the count in timer 0
*
*******************************************************************************/
int timer0_read()
{
  int i;

  i = *(unsigned volatile int *)TIMER0_COUNT;
  return i;
}

/*******************************************************************************
* FUNCTION : timer0_start
*
* ARGUMENTS :
*   VOID
* 
* DESCRIPTION :
*   Start timer 0 after initializing it for 32-bit count and no interrupt.
* 
* OUTPUTS :
*   VOID
*
*******************************************************************************/
void timer0_start()
{
  /* Hold the timer */
  *(unsigned volatile int *)TIMER0_CTRL &= 0xff3f;

  /* Use CPU CLK/4 */
  *(unsigned volatile int *)TIMER0_CTRL |= 0x200;

  /* Set for 32 bit counter */
  *(unsigned volatile int *)TIMER0_PRD  |= 0xffffffff;

  /* Start the timer */
  *(unsigned volatile int *)TIMER0_CTRL |= 0xC0;
}

/*******************************************************************************
* FUNCTION : timer0_init
*
* ARGUMENTS :
*   VOID
*
* DESCRIPTION :
*   Start timer 0 after initializing it for a short period (~13.7 micro seconds)
*   with interrupt.
*
* OUTPUTS :
*   VOID
*
*******************************************************************************/
void timer0_init()
{
  /* Hold the timer */
  *(unsigned volatile int *)TIMER0_CTRL &= 0xff3f;

  /* Use CPU CLK/4 */
  *(unsigned volatile int *)TIMER0_CTRL |= 0x200;

  /* Set for a short period */
  *(unsigned volatile int *)TIMER0_PRD   = 0x200;

  /* Start the timer, enable timer0 int */
  *(unsigned volatile int *)TIMER0_CTRL |= 0x3C0;
}
/* END OF FILE */