GT-King Pro - RS232 - how to use

teacup

Could you please explain how can we use the RS-232 port present in GT-King Pro?
Can it be used for hard brick recovery, aka very low level bootloader flashing, for example in case u-boot gets corrupted?

Can it be used to access u-boot console?
Can it be used to display kernel boot log?
Thanks for any replies.

I have GT-King Pro with S/N starting with SA9HH.
Is any of the released source packages (SDK) compatible with my GT-King Pro model?
Which u-boot source package can I compile and safely flash while keeping android bootable with this model?
Thank you.

spikerguy

Serial port is for boot log,

On Amlogic SOC there is not Hard brick, as it can enter into recovery mode easily as the hardware is designed in such a way that you can use keys to enter into recovery mode where the Amlogic burning tool can detect the device and reflash the OS onto the emmc.

You can use it for u-boot console and kernel boot log yes.  I have been using it to read u-boot logs as well as kernel logs to look for errors when needed.I have been using Bafo USB Serial

I am not an android guy so I cannot answer your SDK and Android uboot question.

teacup

I tried to connect my GT-King Pro to my PC via RS-232 cable (RX to TX, TX to RX and GND to GND) and tried to see something on serial console with minicom, but did not get anything there.
Tried to "interrupt" the boot process by sending some key-strokes right after powerup in minicom, got nothing, system booted normally.

Could you please let me know what are the magic keys to enter u-boot or recovery?
Should I run some flashing tool first to be able to access u-boot console?

So working u-boot is not neccessary to be able to recover the device via amlogic burning tool, meaning there is some kind of primary bootloader in ROM, that can communicate with the burning tool even before u-boot would get loaded?

spikerguy

Hello,
Can you try the steps mentioned in my blogspot.
Using this you should be able to play netflix videos.
How to watch Netflix on Android TV Boxes
Hope this helps.

teacup

Thanks for the interesting netflix blog post.
But I had different questions asked concerning RS-232 u-boot access magic keys - please see above.

teacup

So I finally made it work - getting serial console with uboot and kernel boot logs.
It seems the RS-232 connector of GT-King Pro is wired differently than one could suppose, i.e. to have the same pin outs as the same connector on PC and therefore use RS-232 cross cable for communication. That does not work.

RX and TX pins are already switched on the King Pro connector, so you need a straight RS-232 cable (or wire an adapter to compensate for the cross cable /making it double cross/ as I had to do).
How easy it could be if Beelink just documented the RS-232 connector pins!

spikerguy

I think you're right, but mostly everyone uses Rs-232 to usb convertor adaptor so it is not really needed for documentation unless someone is using direct serial cable which is quite rare these days.

And sorry about that netflix post, looks like forum posted my post in wrong thread, Now I am thinking who was asking for steps to run netflix on tv box lol.

Good you have solved your issue.