pwm._c

这是本人毕业设计的源码部分,主要完成了步进电机的智能控制:采用AVR系列单片机做主空单元,可红外遥控,其中脉冲分配由CPLD实现.

//ICC-AVR application builder : 2006-5-30 11:33:48
// Target : M128
// Crystal: 8.0000Mhz

#include <iom128v.h>
#include <macros.h>







void timer3_init(void)
{
 TCCR3B = 0x00; //stop
 TCNT3H = 0xFF; //setup
 TCNT3L = 0x38;
 OCR3AH = 0x00;
 OCR3AL = 0xC8;
 ICR3H  = 0x00;
 ICR3L  = 0xC8;
 TCCR3A = 0x81;
 TCCR3B = 0x11; //start Timer
}

#pragma interrupt_handler timer3_compa_isr:27
void timer3_compa_isr(void)
{
 OCR3AH = 0x00;
 OCR3AL = 0xC8;
 //compare occured TCNT3=OCR3A
}

#pragma interrupt_handler timer3_ovf_isr:30
void timer3_ovf_isr(void)
{
 //TIMER3 has overflowed
 ICR3H  = (speed*400)/256;
 ICR3L  = (speed*400)%256;
 
 TCNT3H = 0xFF; //reload counter high value
 TCNT3L = 0x38; //reload counter low value
}

//call this routine to initialize all peripherals
void init_devices(void)
{
 //stop errant interrupts until set up
 CLI(); //disable all interrupts
 XDIV  = 0x00; //xtal divider
 XMCRA = 0x00; //external memory
 port_init();
 timer3_init();

 MCUCR = 0x00;
 EICRA = 0x00; //extended ext ints
 EICRB = 0x00; //extended ext ints
 EIMSK = 0x00;
 TIMSK = 0x00; //timer interrupt sources
 ETIMSK = 0x14; //extended timer interrupt sources
 SEI(); //re-enable interrupts
 //all peripherals are now initialized
}