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authorJack Humbert <jack.humb@gmail.com>2016-04-29 22:19:40 -0400
committerJack Humbert <jack.humb@gmail.com>2016-04-29 22:19:40 -0400
commit0656f2fa10e25e160617c3e5d14cfbae35dd9c8d (patch)
treed93e122e84313a89b84ea2a1011093398cf75ab3 /keyboard/atomic/atomic.c
parent9ab7098c834ffe601ad5c39759acfddabbd6373f (diff)
moves backlight functionality to keyboard files and updates template makefile
previously there were two backlight.c files (bad)
Diffstat (limited to 'keyboard/atomic/atomic.c')
-rw-r--r--keyboard/atomic/atomic.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/keyboard/atomic/atomic.c b/keyboard/atomic/atomic.c
index 5e31264e68..3996497161 100644
--- a/keyboard/atomic/atomic.c
+++ b/keyboard/atomic/atomic.c
@@ -57,3 +57,64 @@ void led_set_kb(uint8_t usb_led) {
led_set_user(usb_led);
}
+
+#ifdef BACKLIGHT_ENABLE
+#define CHANNEL OCR1C
+
+void backlight_init_ports()
+{
+
+ // 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));
+ }
+}
+
+#endif \ No newline at end of file