cpldac1.c

示波器DIY全套资料

#include <avr/io.h>
#include "KBDaC1.h"
#include "CPLDaC1.h"

/* Function:  uint8_t CPLD_u8ReadKeys(void)
Description: serially reads one port value (1 bit) and compose result byte value */ 
uint8_t CPLD_u8ReadKeys(void)
{
  uint8_t u8Result;
  uint8_t u8Index;

  DDRC  |= (1<<CPLD_nSerCLK);             /* SerCLK as output */
  DDRC  |= (1<<CPLD_nSerEN);              /* SerEN as output */
  DDRC  |= (1<<CPLD_nSerRDWR);            /* SerRDWR as output */
  DDRD  &= (~(1<<CPLD_nSerDATA));         /* SerDATA as input */
  PORTC &= (~(1<<CPLD_nSerRDWR));         /* RDWR=0, read from CPLD operation */
  PORTC |= (1<<CPLD_nSerEN);              /* EN=1, serial clock disabled, read keys to parallel register */
  PORTC &= (~(1<<CPLD_nSerEN));           /* EN=0, serial clock enabled */
  u8Result = 0;                           /* reset the return value */
  for (u8Index=0; u8Index < 8; u8Index++)
  {
    u8Result>>=1;
    PORTC |= (1<<CPLD_nSerCLK);            /* SerCLK = 1 */
    PORTC &= (~(1<<CPLD_nSerCLK));         /* SerCLK = 0 */
    u8Result |= PIND & (1<<CPLD_nSerDATA); /* Insert the port value to u8Result and shift left 1 position */
  }
  return (u8Result);
}


void CPLD_vWriteDivider(uint8_t u8Prescaler, uint16_t u16Counter)
{
  uint16_t u16MaskC;
  uint8_t u8MaskP;

  DDRC |= (1<<CPLD_nSerCLK);              /* SerCLK as output */
  DDRC |= (1<<CPLD_nSerEN);               /* SerEN as output */
  DDRC |= (1<<CPLD_nSerRDWR);             /* SerRDWR as output */
  DDRD |= (1<<CPLD_nSerDATA);             /* SerDATA as output */
  PORTC |=(1<<CPLD_nSerRDWR);             /* RDWR=1, write to CPLD operation */
  PORTC &= (~(1<<CPLD_nSerEN));           /* EN=0, serial clock enabled */
  u8MaskP = 1<<CPLD_nDivRegSize;
  while (u8MaskP!=0)
  {
    if (u8Prescaler&u8MaskP) 
    {
      PORTD |=(1<<CPLD_nSerDATA);
    }
    else
    {
      PORTD &=(~(1<<CPLD_nSerDATA));
    }
    PORTC |= (1<<CPLD_nSerCLK);           /* SerCLK = 1 */
    PORTC &= (~(1<<CPLD_nSerCLK));        /* SerCLK = 0 */
    u8MaskP >>= 1;
  }

  u16MaskC = 1<<CPLD_nCmpRegSize;

  while (u16MaskC!=0)
  {
    if (u16Counter&u16MaskC) 
    {
      PORTD |=(1<<CPLD_nSerDATA);
    }
    else
    {
      PORTD &=(~(1<<CPLD_nSerDATA));
    }
    PORTC |= (1<<CPLD_nSerCLK);           /* SerCLK = 1 */
    PORTC &= (~(1<<CPLD_nSerCLK));        /* SerCLK = 0 */
    u16MaskC >>= 1;
  }
}