SC20 - GPIO and UART

Hello community,

I’ve bought SMART-3VB_V1.3 Kit based on SC20.
I’m using Android 8.1
How can I open permissions for GPIO and UART modules and use them in a proper way?

Thanks in advance.

hi bro:
your know, when we want read or write a device node, we need have the permission to do that.
So we can use this command to change a device node attribute。 ===> chmod 666 your_device_node

After do that, we still don’t have the permissions, because of the selinux.
we still need modify the policy of the selinux.

You are quectel’s customer. if you need more detail help, please submit a tickets on the e-Service. Thank you.

did you mean you have installed android 8 instead of 7.1.2?

hi bro:
you can’t do that. their are different baseline.

The thing is, even when I am adjusting the init_target,rc (GPIO permissions with chmod 777), and system_app.te and system_service.te, still there is no luck opening and using neither GPIO nor UART through ADB shell or Android JNI Application.
Maybe someone please, can tell me what am I missing?

The same thing on both SDKs, Android 8.1 and Android 7.1.2

Dear Chochavo,

Thanks for contacting Quectel. Since your question is specific to your own situation, the solution might not be referential for other customers, we’d move our discussion off this forum.

Kindly share following details to our support email box( ), we will align local FAE to support you further.

  • Company name / Phone Number:

  • R&D location:

  • Project name (so we can refer to it in the future):

  • Application type:

  • Estimated Annual Units (for series production):

  • Project timeline:

  • Current status:

  • From which distributor do you buy Quectel modules & EVB kits?

  • Do you have EVB kit for this application?

  • Problem description:

Thanks for the replies, the solution was found.
The issues were at SELinux enforcing parameters and lack of permissions in init_target.rc at the compilation.