How to control a GPIO in userspace

[Wjian.1]

Hi：

https://wiki.st.com/stm32mpu/wiki/How_to_control_a_GPIO_in_userspace，compiling the user application according to the wiki example while putting it on the board performs an error,how should I deal with the problem?

Failed to issue GET LINEHANDLE IOCTL (-25)

Failed to issue GPIOHANDLE_SET_LINE_VALUES_IOCTL (-25)

Failed to issue GPIOHANDLE_SET_LINE_VALUES_IOCTL (-25)

Failed to issue GPIOHANDLE_SET_LINE_VALUES_IOCTL (-25)

Failed to issue GPIOHANDLE_SET_LINE_VALUES_IOCTL (-25)

Failed to issue GPIOHANDLE_SET_LINE_VALUES_IOCTL (-25)

Failed to issue GPIOHANDLE_SET_LINE_VALUES_IOCTL (-25)

Failed to issue GPIOHANDLE_SET_LINE_VALUES_IOCTL (-25)

Failed to issue GPIOHANDLE_SET_LINE_VALUES_IOCTL (-25)

Failed to issue GPIOHANDLE_SET_LINE_VALUES_IOCTL (-25)

[mleo]

Hi @Wjian.1​ ,

I tried the example code on DK2 and it runs as expected - the green LED is toggling.

Are you running the example on disco, eval, or custom board?

Are you using exactly the same code or did you modify it, e.g. the different pin?

Best regards,

Milan