led blinker.c

来自「8051试验程序 基础教材」· C语言 代码 · 共 112 行

/**
 * LED Blinker example for the Infineon U-SCALE kit
 * Copyright (C) 2007 IAR Systems.
 *	
 * Permission to use, copy, and modify this software with or without fee
 * is hereby granted, provided that this entire notice is included in
 * all copies of any software which is or includes a copy or
 * modification of this software. 
 *
 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTY. IN PARTICULAR, THE AUTHORS MAKES NO
 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
 * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
 * PURPOSE.
 */

/* Uncomment the #include statement that matches the active device on your U-SCALE */
#include <ioXC866.h>
// #include <ioXC886.h>
// #include <ioXC888.h>

#define   IO_vWritePort(PortName, Data) PortName##_DATA = Data
#define   SFR_PAGE(pg,op) pg+op

#define   _pp0 PORT_PAGE=0  // PORT_PAGE postfix
#define   _pp1 PORT_PAGE=1  // PORT_PAGE postfix
#define   _pp2 PORT_PAGE=2  // PORT_PAGE postfix
#define   _pp3 PORT_PAGE=3  // PORT_PAGE postfix
#define   noSST 0x00        // Switch page without saving

/** IO Init */
void IO_Init(void) {

  SFR_PAGE(_pp1, noSST);         // Switch to page 1
  P1_PUDSEL     =  0xBF;         // Load pullup/pulldown select register
  P1_PUDEN      =  0x00;         // Load pullup/pulldown enable register

  SFR_PAGE(_pp0, noSST);         // Switch to page 0
  P1_DIR        =  0xFF;         // Load direction register
}

/** Main Init */
void MAIN_vInit(void)
{
  ///  Initialization of module 'GPIO'
  IO_Init();

  //   Interrupt Priority
  IP            =  0x00;        // Load Interrupt Priority Register
  IPH           =  0x00;        // Load Interrupt Priority High Register
  IP1           =  0x00;        // Load Interrupt Priority 1 Register
  IPH1          =  0x00;        // Load Interrupt Priority 1 High Register

  IEN0_bit.EA   =  1;		// Globally enable interrupts
}

/**
  Timer 2 Init
  Enable timer 2 interrupts.
*/
void T2_vInit(void) {

  IEN0_bit.ET2         = 1;    // Enable Timer 0 Interrupt
  T2_T2CON_bit.TR2     = 1;    // Run Timer 2
  T2_T2CON_bit.TF2     = 0;    // Reset Interrupt Flag

  T2_T2MOD_bit.T2PRE0  = 1;    // Enable Prescaler
  T2_T2MOD_bit.T2PRE0  = 1;    // Enable Prescaler
  T2_T2MOD_bit.T2PRE0  = 1;    // Enable Prescaler
  T2_T2MOD_bit.PREN    = 0;    // Enable Prescaler

  T2_T2MOD_bit.DCEN    = 1;    // Set counter mode
  T2_T2CON_bit.EXEN2   = 1;    // Set counter mode
}

int main(void)
{
  MAIN_vInit();		// Main Init
  T2_vInit();		// Timer 2 Interrupt Init

  IO_vWritePort(P1, 0x00);	// LED on.
	
  T2_T2L = 0xFF;	// Reset timer low
  T2_T2H = 0xFF;	// Reset timer high
		
  while(1){}; /* stop */
}

/**
  Timer 2 Interrupt.
*/
#pragma vector = timer2_ext
__interrupt void interrupt_1 ()
{
  static char count = 30;	// 30 Interrupts per state change

  if(count-- == 0){		// Change LED state
    if(P1_DATA == 0xFF)
      IO_vWritePort(P1, 0x00); 	// LED on.
    else
      IO_vWritePort(P1, 0xFF); 	// LED off.

    count = 30;			//Reset the counter
  }

  T2_T2L = 0x00;  		// Reset Timer 2 Low
  T2_T2H = 0x00;  		// Reset Timer 2 High

  T2_T2CON_bit.TF2 = 0;    	// Reset Interrupt
}