ccu.c

/***********************************************************************
MODULE:    CAPTURE COMPARE UNIT
VERSION:   1.02
CONTAINS:  Routines for configuring the Capture Compare Unit on the
           P89LPC936
COPYRIGHT: Embedded Systems Academy, Inc. - www.esacademy.com
LICENSE:   May be freely used in commercial and non-commercial code
           without royalties provided this copyright notice remains
           in this file and unaltered
WARNING:   IF THIS FILE IS REGENERATED BY CODE ARCHITECT ANY CHANGES
           MADE WILL BE LOST. WHERE POSSIBLE USE ONLY CODE ARCHITECT
           TO CHANGE THE CONTENTS OF THIS FILE
GENERATED: On "Nov 17 2010" at "02:35:06" by Code Architect 2.06
***********************************************************************/

// SFR description needs to be included
#include <reg936.h>
#include "iTrip.h"
#include "ccu.h"

extern volatile word timerCapture;
extern volatile bit DC;

/***********************************************************************
DESC:    Initializes the Capture Compare Unit
         basic timer, count up
         Period: 4 secs
RETURNS: Nothing
CAUTION: Set EA to 1 after calling to enable interrupts
************************************************************************/
void ccu_init
  (
  void
  )
{
	//Channel A for comparator time out
	CCCRA = 0x01;
    OCRAH = CCU_DC >> 8;
    OCRAL = CCU_DC;

	//channels disabled
	CCCRB = 0x00;
	CCCRC = 0x00;
	CCCRD = 0x00;
	
	// reload value (up counter)
	TOR2H = 0x00;
	TOR2L = 0x00;
	
	// latch shadow registers on next overflow
	TCR21 |= 0x80;
	
	// initial count
	TH2 = 0x00;
	TL2 = 0x00;
	
	// timer prescaler
	// divides CCUCLK by 225, CLK^-1 = 61.035 us, CLK^-1 * 2^16 = 3.99999
	TPCR2H = 0x00;
	TPCR2L = 0xE1;
	  
	// set interrupt priority to 0
	IP1 &= ~0x10;
	IP1H &= ~0x10;

	//Configure and enable overflow and Channel A interrupts
//	TICR2 |= 0x88;
//	ECCU = 1;
	// basic timer, count up
	TCR20 = 0x00;
}

void start_CCU () {
  	// count on	
	TCR20 = 0x01;
}

void stop_CCU () {
	//count off
	TCR20 = 0x00;
}

void ccu_isr
  (
  void
  ) interrupt 11 using 3
{
	//Clear interrupt flag
	TIFR2 &= ~0x88;
//	++timerCapture;
//	DC = 1;
}