FAQS

AIO-3399PRO-JD4 How does Android9 use the ALC5640 codec on the
baseboard?

The system uses RK809 codec by default. If you use ALC5640, you need
to modify the hardware. I2S1 signal pin is changed to I2S0 (CORE-
3399PRO-JD4 does not lead to I2S1), I2C and I2S_CLK do not move, need
to jump off the resistance of R89~R93.


The software is modified as follows:

   **Modified according to the latest code**
   commit 809d8d77b59996770a05f81abff9ff2553773ff7
   Author: Firefly <service@t-firefly.com>
   Date:   Tue Oct 20 15:41:26 2020 +0800

       1.add alc5640 support

   --- a/kernel/arch/arm64/boot/dts/rockchip/rk3399pro-firefly-aiojd4.dtsi
   +++ b/kernel/arch/arm64/boot/dts/rockchip/rk3399pro-firefly-aiojd4.dtsi
   @@ -20,11 +20,11 @@
           };

           rk809-sound {
   -               status = "okay";
   +               status = "disabled";
           };

            rt5640-sound {
   -               status = "disabled";
   +               status = "okay";
                    compatible = "simple-audio-card";
                    simple-audio-card,format = "i2s";
                    simple-audio-card,name = "rockchip,rt5640-codec";

How to adjust HDMI output resolution?

AIO-3399PRO-JD4 HDMI cannot automatically identify display resolution
temporary. Use command below to switch 4K resoultion and flash screen:

   # 4k60:
   setprop persist.sys.resolution.main 3840x2160@60
   # Set sys.display.timeline base on the default num to plus one for updating resolution
   setprop sys.display.timeline 1

Open Root permissions

There are many powerful functions of the Android system that require
root permissions. Developers often encounter permissions problems when
using them. How to enable the root permissions of the system on the
Firefly platform? Firefly has added the function of starting root
privileges in the system. The specific steps are as follows:

Find About device in Settgins apk and click into it;

After clicking on Build number 5 times, it will prompt (you are now a
developer);

Then return to the previous level and click the option Developer
options, and click ROOT access in the options to open the root
authority function.


What should I do if the boot is abnormal and restarts cyclically?

It may be that the power supply current is not enough. Please use a
power supply with a voltage of 12V and a current of 2.5A~3A.

What is the default username and password for Ubuntu?

Username: firefly

Password: firefly

Switch super user sudo -s

Where is the RK3399Pro chip technical manual?

K3399Pro chip technical manual link: [Part1](https://download.t-firef
ly.com/product/RK3399/Docs/Chip%20Specifications/RK3399Pro-
TRM-V1.0/Rockchip%20RK3399Pro%20TRM%20V1.0% 20Part1-20190122.pdf) [Pa
rt2](https://download.t-firefly.com/product/RK3399/Docs/Chip%20Specif
ications/RK3399Pro-TRM-V1.0/Rockchip%20RK3399Pro%20TRM%20V1.0%
20Part2-20190122.pdf)

How to turn off audio in Android system?

For users without a codec module, if the audio-related configuration
is not turned off, the kernel will always report abnormal log
information. There are two ways to turn off the audio:

Disable audioserver in the source code:

   --- a/vendor/rockchip/common/device-vendor.mk
   +++ b/vendor/rockchip/common/device-vendor.mk
   @@ -121,6 +121,8 @@ ifeq ($(strip $(TARGET_BOARD_PLATFORM)), rk3399pro)
    $(call inherit-product-if-exists, vendor/rockchip/common/npu/npu_transfer.mk)
     endif

      -$(call inherit-product-if-exists, vendor/rockchip/common/tinyalsa/tinyalsa.mk)

       $(call inherit-product-if-exists, vendor/rockchip/common/pppoe/pppoe.mk)

Directly delete udio.primary.default.so:

   out/target/product/rk3399pro_firefly_aiojd4/vendor/lib64/hw/audio.primary.default.so

Write number tool to write SN, MAC address

Note:

 If the eMMC erase operation is performed on the development board,
the previously written data will also be cleared.

Windows way

Install RKDevInfoWriteTool  Download link

Select "RPMB" in Settings of RKDevInfoWriteTool

Configure "SN", "WIFI MAC", "LAN MAC", "BT MAC", etc. in the Settings
of RKDevInfoWriteTool as needed

The development board enters loader mode

RKDevInfoWriteTool performs write or read operations

For specific operations, please refer to the PDF document
"RKDevInfoWriteTool User Guide" under the RKDevInfoWriteTool
installation directory.

Linux way

How to write the number of the development board itself

Buildroot enable BR2_PACKAGE_VENDOR_STORAGE

Read and write operations through the vendor_storage command  Download
link  SN  vendor_storage -w VENDOR_SN_ID -t string -i cad895bedb8ee15f
vendor_storage -r VENDOR_SN_ID -t hex -i /dev/null  LAN MAC
vendor_storage -w VENDOR_LAN_MAC_ID -t string -i AABBCCDDEEFF
vendor_storage -r VENDOR_LAN_MAC_ID -t hex -i /dev/null    Others can
be operated according to the prompt of `vendor_storage -h`.

For how to read the application, please refer to the
"vendor_storage_read" function in
"buildroot/package/rockchip/vendor_storage/vendor_storage.c".

On Ubuntu system, if there is no sound after plugging in headphones,
what should I do?

"Menu" -> "Multimedia" -> "PulseAudio Volume Control" ->
"Configuration" -> Select the sound card that is working and turn off
the other sound card.

How to make the system crawl LOG under Android?

"Settings (settings)" -> "About phone (about phone)" -> Click 5 times
"Build number (version number)" -> "Developer options (Developer
options)" -> "Enable logging to save Save)". After the function is
turned on, the folder ".LOGSAVE" will be generated under the root
directory of the system "storage", which includes the system logcat
and kernel kmsg.