vk-hca
commented
3 years ago Yes that would be great. I have collated quite some material I was going to put up here since this opening github but not put it up. Being new to Github I was a bit uncertain about just loading all this research material from other sources up. A lot of it came from using a Chinese search site which was a learning experience in it self.
Like wise I found very little info on line but eventually managed to gather info on the modem chip used, some datasheets etc some are referring to similar chips from the same manufacturer.
I generated a complete circuit of the receiver, created high res pix of the board with the tracks high lighted of the GX6605 receiver I have here. Pretty much it seems to be from application note design on these chips.
I also have the big brother version based on GX6102 which has a cat5 and an extra usb port and more flash and ram capacity which I have been working with. Its easier for me without the wifi requirement. The flash is writable, and the firmware looks for and external NFS mount which I changed to be on my Debian box meaning you can run your own code in the device with out messing with the installed firmware and altering much in the existing flash.
They use the same firmware in both and I found some config tools in source code for their chips. All useful resources of info.
It all runs on busybox, and I have been trying to get their Csky buildroot and Qemu working and generate my own version of busybox so I can create compiled code externally and drop it into busy box while its actually out in the Debian PC hard drive. Getting those tools working also has not been as easy as I hoped but its just a matter of time learning.
Basically all the firmware IO is kernel modules are loaded on boot, then it executes the dvb app. So start the box, telnet in, kill the dvb app process, and you have full run of the box with the io all working. It remains to work out the calls to the various IO modules which remain loaded.
The DVB app they use is generic across models and OEMS, they add their own menus etc. It appeared that menu options can be used from within the dvb code can he hijacked, ie the youtube app can be replaced with your own code. All in all a nice device to work with. I suspect, no matter the make name label and panel on the box, the code will be the same with the OEM look and feel added to the same menu structure.
Because of all of the io provided these boxes it look easy enough to convert into any thing you like by simply replacing the dvb app with some thing of your own built to run from busybox.
The down side is the Csky github only covers the processor not the io peripheral functions on the chip. Meaning to control the dvb modem you need the datasheets on the chip added in, from memory I think its a GX3101. Dont quote me on that.
If you want to code for a normal broadcast stream its demod is ok, I wanted to extract the raw stream as ip data, as used in weather satellite down links wrapped in DVB-MPE which these demods cant provide.
I am happy enough to give you all I have collated and work with you but right now I have partition table issue with the drive its all on, and the machine with the tools to recover it has a bad motherboard and I am all out of time to deal with it for a while.
Because its been pushed down the priority list for now and I have not looked at it for a few months.
I have one GX
xenpac
bansal55
bkzshabbaz
indotronic
danielkucera
Hi there,
i am also trying to mod en existing cheap chinese sat receiver with GX6605 to be able to use it as a development platform for dvb-s2 reception.
i havent found any forum activity on google suiting this subject.
if you like, we can exchange thoughts and experience.