PWM control: channel B didn't appeared in sysfs after canging pin mode

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Pavel Yermolenko

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Sep 15, 2020, 3:02:20 PM9/15/20
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Hello,

I connected two pins on P9 header to EHRPWM0 peripheral (channels A and B).
Channel A is visible whereas B not.

debian@beaglebone:/sys/class/pwm/pwmchip1$ sudo show-pins | sort
......
P9.21 / spi boot in               85 fast rx down 3 pwm 0 out B      ocp/P9_21_pinmux (pinmux_P9_21_pwm_pin)
P9.22 / spi boot clk              84 fast rx down 3 pwm 0 out A      ocp/P9_22_pinmux (pinmux_P9_22_pwm_pin)
......

debian@beaglebone:/sys/class/pwm/pwmchip1$ ls
device  export  npwm  power  pwm-1:0  subsystem  uevent  unexport
debian@beaglebone:/sys/class/pwm/pwmchip1$


pwm-1:1 is missed. Why ?

Sincerely,

Pavel.

Robert Nelson

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Sep 15, 2020, 4:48:01 PM9/15/20
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Did you export channel 1?

debian@bbb-pwr01-ser09:/sys/class/pwm/pwmchip1$ echo 0 > export
debian@bbb-pwr01-ser09:/sys/class/pwm/pwmchip1$ echo 1 > export

Regards,

--
Robert Nelson
https://rcn-ee.com/

Pavel Yermolenko

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Sep 15, 2020, 5:31:35 PM9/15/20
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Thanks !

On Tuesday, September 15, 2020 at 10:48:01 PM UTC+2, RobertCNelson wrote:
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