PWM_CH_CTRL
octrl = ctrl = PWM_READ(sc, PWM_CH_CTRL);
PWM_WRITE(sc, PWM_CH_CTRL, ctrl);
ctrl = PWM_READ(sc, PWM_CH_CTRL);
ctrl = PWM_READ(sc, PWM_CH_CTRL);
PWM_WRITE(sc, PWM_CH_CTRL, ctrl);