/****************************************************************************************
|  Description: LED driver source file
|    File Name: led.c
|
|----------------------------------------------------------------------------------------
|                          C O P Y R I G H T
|----------------------------------------------------------------------------------------
|   Copyright (c) 2011  by Feaser    http://www.feaser.com    All rights reserved
|
|----------------------------------------------------------------------------------------
|                            L I C E N S E
|----------------------------------------------------------------------------------------
| This file is part of OpenBLT. OpenBLT is free software: you can redistribute it and/or
| modify it under the terms of the GNU General Public License as published by the Free
| Software Foundation, either version 3 of the License, or (at your option) any later
| version.
|
| OpenBLT is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
| without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
| PURPOSE. See the GNU General Public License for more details.
|
| You should have received a copy of the GNU General Public License along with OpenBLT.
| If not, see <http://www.gnu.org/licenses/>.
|
| A special exception to the GPL is included to allow you to distribute a combined work 
| that includes OpenBLT without being obliged to provide the source code for any 
| proprietary components. The exception text is included at the bottom of the license
| file <license.html>.
| 
****************************************************************************************/

/****************************************************************************************
* Include files
****************************************************************************************/
#include "header.h"                                    /* generic header               */


/****************************************************************************************
* Macro definitions
****************************************************************************************/
#define LED_TOGGLE_MS  (500)                   /* toggle interval time in millisecodns */


/****************************************************************************************
** NAME:           LedInit
** PARAMETER:      none
** RETURN VALUE:   none
** DESCRIPTION:    Initializes the LED.
**
****************************************************************************************/
void LedInit(void)
{
  /* set io pins for led P1.23 */
  IO1DIR |= 0x00800000;
  /* turn the led off */
  IO1SET  = 0x00800000;
} /*** end of LedInit ***/


/****************************************************************************************
** NAME:           LedToggle
** PARAMETER:      none
** RETURN VALUE:   none
** DESCRIPTION:    Toggles the LED at a fixed time interval.
**
****************************************************************************************/
void LedToggle(void)
{
  static unsigned char led_toggle_state = 0;
  static unsigned long timer_counter_last = 0;
  unsigned long timer_counter_now;

  /* check if toggle interval time passed */
  timer_counter_now = TimerGet();
  if ( (timer_counter_now - timer_counter_last) < LED_TOGGLE_MS)
  {
    /* not yet time to toggle */
    return;
  }
  
  /* determine toggle action */
  if (led_toggle_state == 0)
  {
    led_toggle_state = 1;
    /* turn the LED on */
    IO1CLR =  0x00800000;
  }
  else
  {
    led_toggle_state = 0;
    /* turn the LED off */
    IO1SET =  0x00800000;
  }

  /* store toggle time to determine next toggle interval */
  timer_counter_last = timer_counter_now;
} /*** end of LedToggle ***/


/*********************************** end of led.c **************************************/