LEDC: Add examples/ledc_check.c for check freq and duty (Issue report). (IDFGH-14067)

[IhorNehrutsa]

The ledc_timer_config() does not set the right frequencies. The ledc_channel_config() does not set the right duties.

Tested in v5.2.2 and v5.3.1 Issue report: Freq 1, 2, 3, and 4 are wrong. Duty on freq 80, 200, ... 5000, 10000, 40000000 are wrong.

freq=1     500.00% timer.freq_hz=1, get_freq=6,      0.00% channel.duty=524288, get_duty=524288    timer.duty_resolution=20
freq=2     500.00% timer.freq_hz=2, get_freq=12,     0.00% channel.duty=524288, get_duty=524288    timer.duty_resolution=20
freq=3     166.67% timer.freq_hz=3, get_freq=8,      0.00% channel.duty=524288, get_duty=524288    timer.duty_resolution=20
freq=4     525.00% timer.freq_hz=4, get_freq=25,     0.00% channel.duty=524288, get_duty=524288    timer.duty_resolution=20
freq=5  
freq=70  
freq=80    0.00% timer.freq_hz=80, get_freq=80,      100.00% channel.duty=262144, get_duty=524288  timer.duty_resolution=19
freq=90  
freq=100  
freq=200   0.00% timer.freq_hz=200, get_freq=200,    100.00% channel.duty=131072, get_duty=262144  timer.duty_resolution=18
freq=300  
freq=400   0.00% timer.freq_hz=400, get_freq=400,    100.00% channel.duty=65536, get_duty=131072   timer.duty_resolution=17
freq=500  
freq=600  
freq=700   0.14% timer.freq_hz=700, get_freq=701,    100.00% channel.duty=32768, get_duty=65536    timer.duty_resolution=16
freq=800  
freq=1000  
freq=2000  0.15% timer.freq_hz=2000, get_freq=1997,  100.00% channel.duty=16384, get_duty=32768    timer.duty_resolution=15
freq=3000  0.07% timer.freq_hz=3000, get_freq=2998,  100.00% channel.duty=8192, get_duty=16384    timer.duty_resolution=14
freq=4000  
freq=5000  0.00% timer.freq_hz=5000, get_freq=5000,  100.00% channel.duty=4096, get_duty=8192    timer.duty_resolution=13
freq=6000  
freq=9000  
freq=10000  0.00% timer.freq_hz=10000, get_freq=10000, 100.00% channel.duty=2048, get_duty=4096    timer.duty_resolution=12
freq=20000  
freq=30000000  
freq=40000000  0.00% timer.freq_hz=40000000, get_freq=40000000, 200.00% channel.duty=1, get_duty=3    timer.duty_resolution=1
END.

[github-actions[bot]]

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[IhorNehrutsa]

For testing ledc_timer_set(timer.speed_mode, timer.timer_num, divider, timer.duty_resolution, timer.clk_cfg)) function you need Add LEDC ledc_calculate_divisor() function to the /driver/ledc.h. #14884