123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081 |
- #include "jd45.h"
- __attribute__ ((weak))
- void matrix_init_user(void) {
- };
- __attribute__ ((weak))
- void matrix_scan_user(void) {
- };
- #define CHANNEL OCR1C
- void backlight_init_ports(void)
- {
- // Setup PB7 as output and output low.
- DDRB |= (1<<7);
- PORTB &= ~(1<<7);
-
- // Use full 16-bit resolution.
- ICR1 = 0xFFFF;
- // I could write a wall of text here to explain... but TL;DW
- // Go read the ATmega32u4 datasheet.
- // And this: http://blog.saikoled.com/post/43165849837/secret-konami-cheat-code-to-high-resolution-pwm-on
-
- // Pin PB7 = OCR1C (Timer 1, Channel C)
- // Compare Output Mode = Clear on compare match, Channel C = COM1C1=1 COM1C0=0
- // (i.e. start high, go low when counter matches.)
- // WGM Mode 14 (Fast PWM) = WGM13=1 WGM12=1 WGM11=1 WGM10=0
- // Clock Select = clk/1 (no prescaling) = CS12=0 CS11=0 CS10=1
-
- TCCR1A = _BV(COM1C1) | _BV(WGM11); // = 0b00001010;
- TCCR1B = _BV(WGM13) | _BV(WGM12) | _BV(CS10); // = 0b00011001;
- backlight_init();
- }
- void backlight_set(uint8_t level)
- {
- if ( level == 0 )
- {
- // Turn off PWM control on PB7, revert to output low.
- TCCR1A &= ~(_BV(COM1C1));
- CHANNEL = 0x0;
- // Prevent backlight blink on lowest level
- PORTB &= ~(_BV(PORTB7));
- }
- else if ( level == BACKLIGHT_LEVELS )
- {
- // Prevent backlight blink on lowest level
- PORTB &= ~(_BV(PORTB7));
- // Turn on PWM control of PB7
- TCCR1A |= _BV(COM1C1);
- // Set the brightness
- CHANNEL = 0xFFFF;
- }
- else
- {
- // Prevent backlight blink on lowest level
- PORTB &= ~(_BV(PORTB7));
- // Turn on PWM control of PB7
- TCCR1A |= _BV(COM1C1);
- // Set the brightness
- CHANNEL = 0xFFFF >> ((BACKLIGHT_LEVELS - level) * ((BACKLIGHT_LEVELS + 1) / 2));
- }
- }
- void matrix_init_kb(void) {
- #ifdef BACKLIGHT_ENABLE
- backlight_init_ports();
- #endif
- matrix_init_user();
- };
- void matrix_scan_kb(void) {
- matrix_scan_user();
- };
|