ADC and PWM access on BeagleV Fire

I am using the cape(both cape_for_uarts and robotics) mentioned here:

I am using the following process:

ls /sys/class/pwm/

pwmchip0 pwmchip16 pwmchip32

echo 0 | sudo tee /sys/class/pwm/pwmchip0/pwm0/enable

echo 20000000 | sudo tee /sys/class/pwm/pwmchip0/pwm0/period

echo 1500000 | sudo tee /sys/class/pwm/pwmchip0/pwm0/duty_cycle

echo 1 | sudo tee /sys/class/pwm/pwmchip0/pwm0/enable

I don’t know which physical pin it is referring as pwmchip0/pwm0?

My primary problem is I want to change the duty cycle and frequency of PWM and apply it on a specific pin. Any help would be really appreciated.
ADC part, I have been able to figure out myself.
TIA.