54 rader
1.3 KiB
C
54 rader
1.3 KiB
C
// http://blog.saikoled.com/post/43165849837/secret-konami-cheat-code-to-high-resolution-pwm-on
|
|
#include <avr/io.h>
|
|
#include "backlight.h"
|
|
|
|
#define FET OCR1A
|
|
|
|
uint8_t led_counter = 0;
|
|
uint8_t led_level = 0;
|
|
|
|
|
|
void backlight_init_ports()
|
|
{
|
|
DDRB |= (1<<5);
|
|
PORTB &= ~(1<<5);
|
|
|
|
TCCR1A = _BV(COM1A1) | _BV(WGM11); // = 0b10000010;
|
|
TCCR1B = _BV(WGM13) | _BV(WGM12) | _BV(CS10); // = 0b00011001;
|
|
|
|
ICR1 = 0xFFFF;
|
|
|
|
FET = 0x0000;
|
|
|
|
backlight_init();
|
|
}
|
|
|
|
void backlight_set(uint8_t level)
|
|
{
|
|
if ( level == 0 )
|
|
{
|
|
// Turn off PWM control on PB5, revert to output low.
|
|
TCCR1A &= ~(_BV(COM1A1));
|
|
FET = 0x0000;
|
|
// Prevent backlight blink on lowest level
|
|
PORTB &= ~(_BV(PORTB5));
|
|
}
|
|
else if ( level == BACKLIGHT_LEVELS )
|
|
{
|
|
// Prevent backlight blink on lowest level
|
|
PORTB &= ~(_BV(PORTB5));
|
|
// Turn on PWM control of PB5
|
|
TCCR1A |= _BV(COM1A1);
|
|
// Set the brightness
|
|
FET = 0xFFFF;
|
|
}
|
|
else
|
|
{
|
|
// Prevent backlight blink on lowest level
|
|
PORTB &= ~(_BV(PORTB5));
|
|
// Turn on PWM control of PB5
|
|
TCCR1A |= _BV(COM1A1);
|
|
// Set the brightness
|
|
FET = 0xFFFF >> ((BACKLIGHT_LEVELS - level) * ((BACKLIGHT_LEVELS + 1) / 2));
|
|
}
|
|
} |