发现M16的TC1的重大缺陷！！！！！
本人用M16的TC1产生PWM信号，并且在产生信号的同时不断改变频率，但变频幅度很小，这时就出现一个很令人费解的现象，PWM信号会不时有断开的现象
PWM频率：28KHz
OC1A、OC1B双路输出：想得到的信号是：如图正常的波形
但是一旦改变频率，两路的信号会随即的中断6.5ms左右,如图断开的波形，不知其解，各位高手请指教
程序：
// Target : M16
// Crystal: 10.000Mhz
#include
#include
void port_init(void)
{
PORTA = 0x00;
DDRA = 0x00;
PORTB = 0x00;
DDRB = 0x00;
PORTC = 0x00; //m103 output only
DDRC = 0x00;
PORTD = 0x00;
DDRD = 0b00110000;
}
//TIMER1 initialize - prescale:1
// WGM: 8) PWM phz freq correct, TOP=ICRn
// desired value: 28KHz
// actual value: 28.090KHz (0.3%)
void timer1_init(void)
{
TCCR1B = 0x00; //stop
TCNT1H = 0xFF; //setup
TCNT1L = 0x4E;
OCR1AH = 0x00;
OCR1AL = 0xB2-0x50;
OCR1BH = 0x00;
OCR1BL = 0x50;
ICR1H = 0x00;
ICR1L = 0xB2;
TCCR1A = 0xB0;
TCCR1B = 0x11; //start Timer
}
//call this routine to initialize all peripherals
void init_devices(void)
{
//stop errant interrupts until set up
CLI(); //disable all interrupts
port_init();
timer1_init();
MCUCR = 0x00;
GICR = 0x00;
TIMSK = 0x00; //timer interrupt sources
SEI(); //re-enable interrupts
//all peripherals are now initialized
}
void Delay(unsigned int t)
{
unsigned int i,j;
for(i=0;i9)i=0;
Delay(100); //延时
ICR1L=ICR1L_+i; //改变频率
}
}
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