君正X1000 PWM4蜂鸣器该如何调试?
我kernel配置如下:
Device Drivers  --->
    Input device support  ---> 
        *   Miscellaneous devices  --->
        *    PWM beeper support (NEW)
->Device Drivers
    -> Pulse-Width Modulation (PWM) Support (PWM [=y]) 
        --- Pulse-Width Modulation (PWM) Support
        *   JZPWM support for LED or Beeper drivers
        *   JZ PWM driver  
        *** JZ PWM function pinselect *** 
         *    GPIO Port pwm0       
         *    GPIO Port pwm4
应用上需要什么操作?大神们方便帮忙看下,非常感谢!
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后来一搜, 这位网友讲得非常详细
君正X系列开发11---pwm配置、分析
https://blog.csdn.net/cyf15238622067/article/details/80215345
如果pwm驱动蜂鸣器,配置
Device Drivers --->
Input device support --->
[ *] Miscellaneous devices --->< * > PWM beeper support (NEW)
操作如下:
#
# echo timer > /sys/class/leds/leds_pwm4/trigger
# echo none > /sys/class/leds/leds_pwm4/trigger
# echo 255 > /sys/class/leds/leds_pwm4/trigger
sh: write error: Invalid argument
# echo 255 > /sys/class/leds/leds_pwm4/brightness
# echo 0 > /sys/class/leds/leds_pwm4/brightness
# echo 255 > /sys/class/leds/leds_pwm4/brightness
# echo 0 > /sys/class/leds/leds_pwm4/brightness
# echo 255 > /sys/class/leds/leds_pwm4/brightness# echo 0 > /sys/class/leds/leds_pwm4/brightness
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