43 lines
830 B
C
43 lines
830 B
C
#include "17.h"
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int pwm_level;
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void backlight_init_ports(void) {
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// Set C7 to output
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DDRC |= (1<<7);
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// Initialize the timer
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TC4H = 0x03;
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OCR4C = 0xFF;
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TCCR4A = 0b10000010;
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TCCR4B = 0b00000001;
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}
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void backlight_set(uint8_t level) {
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// Determine the PWM level
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switch (level)
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{
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case 0:
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// 33%
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pwm_level = 0x54;
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break;
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case 1:
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// 66%
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pwm_level = 0xA8;
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break;
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case 2:
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// 100%
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pwm_level = 0xFF;
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break;
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case 3:
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// 0%
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pwm_level = 0x00;
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break;
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default:
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xprintf("Unknown level: %d\n", level);
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}
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// Write the PWM level to the timer
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TC4H = pwm_level >> 8;
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OCR4A = 0xFF & pwm_level;
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}
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