Mikroelektronika MIKROE-742 데이터 시트

The example changes PWM duty ratio continually by pressing buttons on PORTC (0-3). If LED is
connected to PORTB.1 or PORTB.2 ,you can observe the gradual change of emitted light. This
example is written for ATmega168. This AVR MCU has only Timer/Counter1 split over two chan-
nels A and B. In this example we are changing the duty ratio on both of these channels.

program PWM16bit_Test;

var current_duty : byte;

current_duty1 : byte;

DDRC.B0 := 0;                  // Set PORTC pin 0 as input

DDRC.B1 := 0;                  // Set PORTC pin 1 as input

DDRC.B2 := 0;                  // Set PORTC pin 2 as input

DDRC.B3 := 0;                  // Set PORTC pin 3 as input

current_duty := 255;           // initial value for current_duty

current_duty1 := 255;          // initial value for current_duty

DDRB.B1 := 1;                   // Set PORTB pin 1 as output pin for the PWM

(according to datasheet)

DDRB.B2 := 1;                // Set PORTB pin 2 as output pin for the PWM

(according to datasheet)
PWM16bit_Init(_PWM16_FAST_MODE_9BIT, _PWM16_PRESCALER_16bit_1, _PWM16_INVERTED,

255, 1);

while TRUE do

if (PINC.B0 <> 0) then

// Detect if PORTC pin 0 is pressed

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- SOFTWARE AND HARDWARE SOLUTIONS FOR EMBEDDED WORLD

CHAPTER 6

procedure PWM16_Stop(timer : byte);

Nothing.

Stops the PWM-16bit module, connected to Timer/Counter set in this stop function. 

MCU must have CMO module to use this library. Like in PWM16bit_Start
before, PWM16bit_Init must be called before using this routine , otherwise it will
have no effect as the PWM module is not running. 

PWM16bit_Stop(_TIMER1 );

// Stops the PWM-16bit module on

Timer/Counter1

or

PWM16bit_Stop(_TIMER3 );

// Stops the PWM-16bit module on

Timer/Counter3