/** * Backlighting code for PS2AVRGB boards (ATMEGA32A) * Kenneth A. (github.com/krusli | krusli.me) */ #include "backlight.h" #include "quantum.h" #include <avr/pgmspace.h> #include <avr/interrupt.h> #include "backlight_custom.h" #include "breathing_custom.h" // DEBUG #include <stdlib.h> #include <stdio.h> // Port D: digital pins of the AVR chipset #define NUMLOCK_PORT (1 << 0) // D0 #define CAPSLOCK_PORT (1 << 1) // D1 #define BACKLIGHT_PORT (1 << 4) // D4 #define SCROLLLOCK_PORT (1 << 6) // D6 #define TIMER_CLK_DIV64 0x03 ///< Timer clocked at F_CPU/64 #define TIMER1PRESCALE TIMER_CLK_DIV64 ///< timer 1 prescaler default #define TIMER_PRESCALE_MASK 0x07 ///< Timer Prescaler Bit-Mask #define PWM_MAX 0xFF #define TIMER_TOP 255 // 8 bit PWM extern backlight_config_t backlight_config; /** * References * Port Registers: https://www.arduino.cc/en/Reference/PortManipulation * TCCR1A: https://electronics.stackexchange.com/questions/92350/what-is-the-difference-between-tccr1a-and-tccr1b * Timers: http://www.avrbeginners.net/architecture/timers/timers.html * 16-bit timer setup: http://sculland.com/ATmega168/Interrupts-And-Timers/16-Bit-Timer-Setup/ * PS2AVRGB firmware: https://github.com/showjean/ps2avrU/tree/master/firmware */ // @Override // turn LEDs on and off depending on USB caps/num/scroll lock states. __attribute__ ((weak)) void led_set_user(uint8_t usb_led) { if (usb_led & (1 << USB_LED_NUM_LOCK)) { // turn on DDRD |= NUMLOCK_PORT; PORTD |= NUMLOCK_PORT; } else { // turn off DDRD &= ~NUMLOCK_PORT; PORTD &= ~NUMLOCK_PORT; } if (usb_led & (1 << USB_LED_CAPS_LOCK)) { DDRD |= CAPSLOCK_PORT; PORTD |= CAPSLOCK_PORT; } else { DDRD &= ~CAPSLOCK_PORT; PORTD &= ~CAPSLOCK_PORT; } if (usb_led & (1 << USB_LED_SCROLL_LOCK)) { DDRD |= SCROLLLOCK_PORT; PORTD |= SCROLLLOCK_PORT; } else { DDRD &= ~SCROLLLOCK_PORT; PORTD &= ~SCROLLLOCK_PORT; } } #ifdef BACKLIGHT_ENABLE // sets up Timer 1 for 8-bit PWM void timer1PWMSetup(void) { // NOTE ONLY CALL THIS ONCE // default 8 bit mode TCCR1A &= ~(1 << 1); // cbi(TCCR1A,PWM11); <- set PWM11 bit to HIGH TCCR1A |= (1 << 0); // sbi(TCCR1A,PWM10); <- set PWM10 bit to LOW // clear output compare value A // outb(OCR1AH, 0); // outb(OCR1AL, 0); // clear output comparator registers for B OCR1BH = 0; // outb(OCR1BH, 0); OCR1BL = 0; // outb(OCR1BL, 0); } bool is_init = false; void timer1Init(void) { // timer1SetPrescaler(TIMER1PRESCALE) // set to DIV/64 (TCCR1B) = ((TCCR1B) & ~TIMER_PRESCALE_MASK) | TIMER1PRESCALE; // reset TCNT1 TCNT1H = 0; // outb(TCNT1H, 0); TCNT1L = 0; // outb(TCNT1L, 0); // TOIE1: Timer Overflow Interrupt Enable (Timer 1); TIMSK |= _BV(TOIE1); // sbi(TIMSK, TOIE1); is_init = true; } void timer1UnInit(void) { // set prescaler back to NONE (TCCR1B) = ((TCCR1B) & ~TIMER_PRESCALE_MASK) | 0x00; // TIMERRTC_CLK_STOP // disable timer overflow interrupt TIMSK &= ~_BV(TOIE1); // overflow bit? setPWM(0); is_init = false; } // handle TCNT1 overflow //! Interrupt handler for tcnt1 overflow interrupt ISR(TIMER1_OVF_vect, ISR_NOBLOCK) { // sei(); // handle breathing here #ifdef BACKLIGHT_BREATHING if (is_breathing()) { custom_breathing_handler(); } #endif // TODO call user defined function } // enable timer 1 PWM // timer1PWMBOn() void timer1PWMBEnable(void) { // turn on channel B (OC1B) PWM output // set OC1B as non-inverted PWM TCCR1A |= _BV(COM1B1); TCCR1A &= ~_BV(COM1B0); } // disable timer 1 PWM // timer1PWMBOff() void timer1PWMBDisable(void) { TCCR1A &= ~_BV(COM1B1); TCCR1A &= ~_BV(COM1B0); } void enableBacklight(void) { DDRD |= BACKLIGHT_PORT; // set digital pin 4 as output PORTD |= BACKLIGHT_PORT; // set digital pin 4 to high } void disableBacklight(void) { // DDRD &= ~BACKLIGHT_PORT; // set digital pin 4 as input PORTD &= ~BACKLIGHT_PORT; // set digital pin 4 to low } void startPWM(void) { timer1Init(); timer1PWMBEnable(); enableBacklight(); } void stopPWM(void) { timer1UnInit(); disableBacklight(); timer1PWMBDisable(); } void b_led_init_ports(void) { /* turn backlight on/off depending on user preference */ #if BACKLIGHT_ON_STATE == 0 // DDRx register: sets the direction of Port D // DDRD &= ~BACKLIGHT_PORT; // set digital pin 4 as input PORTD &= ~BACKLIGHT_PORT; // set digital pin 4 to low #else DDRD |= BACKLIGHT_PORT; // set digital pin 4 as output PORTD |= BACKLIGHT_PORT; // set digital pin 4 to high #endif timer1PWMSetup(); startPWM(); #ifdef BACKLIGHT_BREATHING breathing_enable(); #endif } void b_led_set(uint8_t level) { if (level > BACKLIGHT_LEVELS) { level = BACKLIGHT_LEVELS; } setPWM((int)(TIMER_TOP * (float) level / BACKLIGHT_LEVELS)); } // called every matrix scan void b_led_task(void) { // do nothing for now } void setPWM(uint16_t xValue) { if (xValue > TIMER_TOP) { xValue = TIMER_TOP; } OCR1B = xValue; // timer1PWMBSet(xValue); } #endif // BACKLIGHT_ENABLE