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Title: No HDMI output on Firefly-RK3399 [Print This Page]
Author: clive    Time: 10/31/2018 20:01
Title: No HDMI output on Firefly-RK3399
I have just tried starting my new Firefly RH3399 board for the first time, without success. The blue LED comes on and the optical socket has a red LED showing, but nothing is displayed on the HDMI monitor.

I have plugged in:
-       The fan on the heatsink
-       USB keyboard
-       USB mouse
-       HDMI converter lead to DVI monitor
-       Ethernet
-       Serial/USB converter, to host port on Linux PC
-       USB-C, to host port on a Linux PC
-       12V power plug
-       (No antennae connected)

The monitor is happy that there is a DVI connection. I have tested the monitor and HDMI/DVI convertor lead using the HDMI output on a Windows laptop, and it works.

I can detect the Firefly on the network. The local DHCP server on my network has assigned it an IP address, so I can ping it. I see that the Firefly's Ethernet MAC address is 92:AD:30:72:9C:27 (a "private" MAC address). I tried connecting using telnet and ssh, but for both I got "Connection refused".

I set up minicom on a Linux workstation, on ttyUSB0 at 1500000 8N1, but get no response when I type on the terminal. I also tried sending <BREAK> H, which would normally give me a response on a Linux target, but I assume Firefly is running Android by default and possibly SysRq is disabled.

I pressed the power button momentarily, and the blue LED went off. I pressed it again and the LED came on again.

I tried momentarily pressing RESET, then quickly typing on the serial debug terminal, but nothing happened. (I hoped to get into U-Boot).

Can anybody help me get an HDMI display working, help me establish communication over Ethernet and the serial port?

Also do I need an M.2 SATA adapter board (for SATA HDD)? None was provided in the kit, although the assembly diagram does show a HDD mounted on the bottom acrylic plate.
Author: leungÏÈÉ­    Time: 11/1/2018 09:41
You can use adb to comunicate with board.
Network adb just setprop below and adb connnect 3399IP .
setprop service.adb.tcp.port 5555
setprop persist.internet.adb.enable 1
Author: clive    Time: 11/7/2018 01:29
Thanks for your reply. However, I need to enable Ethernet debugging on the board first, and I couldn't do that with no display and no other way to communicate with the board.

I found that the board is fussy about the type or resolution of the monitor.  When the monitor cannot be supported, it seems the Firefly-RK3399 does not inform the user through a "beep code" or flashing LED code, but the display just stays dark.  It did not work with a 1600x1200 or a 1920x1200 monitor, but a 1920x1080 did work.  A 4k monitor also worked.

Is there any documentation about supported monitor specifications?
Author: leungÏÈÉ­    Time: 11/7/2018 11:39
Last edited by leungÏÈÉ­ In 11/9/2018 10:10 Editor
clive Posted at 11/7/2018 01:29
Thanks for your reply. However, I need to enable Ethernet debugging on the board first, and I couldn ...

RK3399 support CEA mode resolution(TV) . Detail you can google it.
And it might help you .  Diff between CEA and DMT
Author: clive    Time: 11/9/2018 01:56
That was slightly helpful, but did not give a list of modes actually supported by the board.  To answer my own question, I did this:

$ adb connect 10.120.35.75
rtt min/avg/max/mdev = 0.793/0.986/1.360/0.265 ms
* daemon not running. starting it now on port 5037 *
* daemon started successfully *
connected to 10.120.35.75:5555
$ adb shell
rk3399_firefly_box:/ $ ls /sys/class                                          
android_usb   dma         iommu    pci_bus      rkvr         spi_master   
arvo          drm         isku     phy          rkwifi       spidev      
ata_device    extcon      kone     pmsg         rtc          switch      
ata_link      firmware    koneplus power_supply rtk_btusb    thermal      
ata_port      flashlight  konepure ppp          ryos         timed_output
backlight     gpio        kovaplus pps          savu         tty         
bdi           graphics    leds     ptp          scsi_changer udc         
block         hidraw      mdio_bus pwm          scsi_device  video4linux  
bluetooth     hwmon       mem      pyra         scsi_disk    vpu_service  
bsg           i2c-adapter misc     rc           scsi_generic xt_idletimer
devfreq       i2c-dev     mmc_host regulator    scsi_host    zram-control
devfreq-event ieee80211   net      rfkill       sensor_class
display       input       nvme     rkvdec       sound        
rk3399_firefly_box:/ $ ls /sys/class/drm
card0 card0-DP-1 card0-HDMI-A-1 controlD64 renderD128 version
rk3399_firefly_box:/ $ ls /sys/class/drm/card0-HDMI-A-1/
audioformat device dpms edid enabled mode modes power status subsystem uevent
rk3399_firefly_box:/ $ ls -l /sys/class/drm/card0-HDMI-A-1/mode*
-r--r--r-- 1 root root 4096 2013-01-19 11:00 /sys/class/drm/card0-HDMI-A-1/mode
-r--r--r-- 1 root root 4096 2013-01-19 11:00 /sys/class/drm/card0-HDMI-A-1/modes
rk3399_firefly_box:/ $ cat /sys/class/drm/card0-HDMI-A-1/mode
1920x1080p60
rk3399_firefly_box:/ $ cat /sys/class/drm/card0-HDMI-A-1/modes
1920x1080p75
1920x1080p60
1920x1080p60
1920x1080i60
1920x1080i60
1920x1080p50
1920x1080i50
1680x1050p60
1280x1024p60
1440x900p60
1280x800p60
1152x864p75
1280x720p60
1280x720p60
1280x720p50
1024x768p70
1024x768p60
800x600p60
800x600p56
720x576p50
720x480p60
720x480p60
640x480p67
640x480p60
640x480p60
720x400p70
rk3399_firefly_box:/ $


By the way, if you are trying out the board with an HDMI monitor for the first time, you don't need anything else plugged in except the HDMI monitor, the heatsink fan and the 12V power input.  If the monitor works you should see the Firefly logo within a couple of seconds.
Author: andrewsinn    Time: 1/27/2026 02:04
Ich habe ähnliche Probleme mit meinem Firefly-RK3399 Board gehabt. Es scheint, dass viele Nutzer Schwierigkeiten haben, eine HDMI-Verbindung herzustellen. Ich empfehle, zuerst sicherzustellen, dass alle Verbindungen korrekt sind und dass der Monitor ordnungsgemäß funktioniert. Wenn du die Möglichkeit hast, teste es mit einem anderen HDMI-Kabel oder Monitor. Es könnte auch hilfreich sein, die Firmware des Boards zu ¨¹berpr¨¹fen oder eventuell ein Update durchzuf¨¹hren, falls das möglich ist. Falls du Unterst¨¹tzung in der Schweiz benötigst, findest du n¨¹tzliche Ressourcen und Zubehör auf dieser Website: https://spinmama.ch. Dort gibt es möglicherweise auch spezifische Anleitungen oder Produkte, die dir helfen können, dein Problem zu lösen. Denke daran, die richtigen Treiber und Tools f¨¹r die Kommunikation ¨¹ber Ethernet und die serielle Verbindung zu installieren. Viel Erfolg!
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