Mikroelektronika MIKROE-350 Fiche De Données

The example changes PWM duty ratio on pin PB3 continually. If LED is connected
to PB3, you can observe the gradual change of emitted light.

program PWM_Test

dim current_duty as byte

current_duty1 

main:

DDB0_bit = 0                    ' Set PORTB pin 0 as input

DDB1_bit = 0                    ' Set PORTB pin 1 as input

DDC0_bit = 0                    ' Set PORTC pin 0 as input

DDC1_bit = 0                    ' Set PORTC pin 1 as input

current_duty  = 127             ' initial value for current_duty
current_duty1 = 127             ' initial value for current_duty

DDB3_bit = 1                    ' Set PORTB pin 3 as output pin

for the PWM (according to datasheet)

DDD7_bit = 1                    ' Set PORTD pin 7 as output pin

for the PWM1 (according to datasheet)

PWM_Init(_PWM_PHASE_CORRECT_MODE, _PWM_PRESCALER_8,

_PWM_NON_INVERTED, 127)

PWM1_Init(_PWM1_PHASE_CORRECT_MODE, _PWM1_PRESCALER_8,

_PWM1_NON_INVERTED, 127)

while TRUE                          ' Endless loop

if (PINB0_bit <> 0) then ' Detect if PORTB pin 0 is pressed

Delay_ms(40)      ' Small delay to avoid deboucing effect
Inc(current_duty)               ' Increment duty ratio

PWM_Set_Duty(current_duty)      ' Set incremented duty

if (PINB1_bit <> 0) then

' Detect if PORTB pin 1 is pressed

Delay_ms(40)     ' Small delay to avoid deboucing effect
Dec(current_duty)               ' Decrement duty ratio

PWM_Set_Duty(current_duty)      ' Set decremented duty ratio

if (PINC0_bit <> 0) then

' Detect if PORTC pin 0 is pressed

Delay_ms(40)       ' Small delay to avoid deboucing effect
Inc(current_duty1)              ' Increment duty ratio

PWM1_Set_Duty(current_duty1)    ' Set incremented duty

315

- SOFTWARE AND HARDWARE SOLUTIONS FOR EMBEDDED WORLD

CHAPTER 6