使用适用于LinuxDVB的CX24116的廉价DVB-S2卫星调谐器卫星接收器_C_源码_下载.zip

# Linux DVB-S2 NIM Sat-Tuner CX24116 **What is this ?** Its a hardware and software project, building a **satellite tuner** to be used with **Linux DVB**. Something like the ***MiniTiouner***.  ## Overview This Satellite Receiver connects to a linux computer via USB cable. It will be detected by linux-kernel as a "DVBWorld DW2104 USB2.0" DVB-Tuner-device. Its basicly a clone. Components used: - **Sharp BSBE2-401A NIM Tuner** (CX24116/8) from ALI for about 7 $. (Tuner is from 2008, used fe. in dreambox) - **CY7C68013A FX2LP LCsoft-Board** USB controller from ALI for about 3 $ - salvaged **old SatReceiver case** with powersupply for free. - some **additional circuitry** for powersupply and LNB supply. - **connects to a Linux-machine via USB** Software: - **firmware** for the LCsoft USB board and the CX24116/8 demodulator/tuner. ## Linux DVB API The Linux DVB framework dates back to around 2009 with not much improvement ever since. At that time a couble of Sat-Tuners came on the market and Linux implemented support for them. Using the Linux DVB framework has the advantage that you do not need to write one line of code. Its all there. Use Kaffeine, TvHeadEnd or VLC to watch television. I was especially looking for a Tuner whos chipset was supported by the Linux Kernel. Eh Viola inexpensive Sharp Tuner turned up having the CX24116/8 chipset. It is a **NIM(Network Interface Module) Tuner**, meaning it has a Tuner(cx24118) and a Demodulator Chip(cx24116) in it. So it outputs the MPEG TS stream from the tuned transponder. Now i had to look into the list of supported devices for Linux DVB-S2 USB: - "DVBWorld DW2104 USB2.0" - exactly the DVBWorld2104C model. Ok, now i had to design my circuit such that the resulting device immitates a "DVBWorld DW2104 USB2.0" product, so the Kernel will accepts it. The Linux kernel needs two firmware files for this SatReceiver: - **dvb-fe-cx24116.fw** = code for the **cx24116 internal processor** V1.26.90.0 , to do automated tuning etc. - **dvb-usb-dw2104.fw** = code for the **fx2lp Cypress chip**, custom version, USB interface to support streaming and i2c transfer to/from cx24116. These two files reside in Linux under **/lib/firmware** and are downloaded on USB connect by the kernel. ## The Circuit general function blocks: DISH--LNB--COAX-CABLE--**[NIM-TUNER--USB-INTERFACE]**--USB-CABLE--LINUX-MACHINE The original DVBWORLD device also uses the Cypress FX2LP Chip, so the LCsoft-board will do the USB interface job. The original firmware "dvb-usb-dw2104.fw" cannot be used, as my HW-design is different. (at least i could not find a schematic for the DVBWORLD device to do an exact copy.) So the only software that needs to be developed was the one for the FX2LP Chip, replacing the "dvb-usb-dw2104.fw". All i2c-control transfer is done via USB Endpoint 0 and it is very important to get this right, otherwise you wonder why things not working. There is a pdf with the **schematic**. ## Powersupply for the Tuner and LNB The salvaged receiver case provided already a switching power supply with 5V and 23V, how handy ;) The cx24116 is taking 1.2V and approx. 500mA. from 5V The LNB needs 13 or 18V at around 100mA. from 23V For the 3.3V i took a standard LM1117 LDO regulator. from 5V. For the 1.2V i took an SMPS i had available, but also a LM317 can be used as 1.2V is the minimum voltage it can deliver. For the LNB the LM317 is ideal as the voltage switching is easy to implement. LM317 need heatsink. As for the FX2LP LCsoft-board, i disconnected the USB-side 5V supply and hooked the board up to the internal 5V supply. (may not be necessary) ## Software I wrote a custom version of the "dvb-usb-dw2104.fw" firmware for the fx2lp controller. To get Linux-DVB to operate this device, you need to install the following 2 files: - copy "dvb-usb-dw2104.fw" and "dvb-fe-cx24116.fw" to /lib/firmware in Linux. Also you need to flash the fx2lp chip once: - flash the "fx2lp.hex" file once to the LCsoft-board eeprom. (using the CyControl.exe in tools) The custom firmware "dvb-usb-dw2104.fw" features the two onboard Leds to indicate: - Led1 : blinking = streaming is on; constantly on = no data from tuner, constantly off = host not reading - Led2 : on = Host not reading USB stream, ie. change channels; off = all ok. I havent included the "dvb-usb-dw2104.fw" firmware **sourcecode**, but can do on request. Thats it . ## Ideas As DVB-S2X seems to be dead, this DVB-S2 receiver would serve as a nice Sat-Frontend for the raspberry pi/tvheadend. I was reading about the MiniTiouner project on amsat-dl.org forum, hmm, maybe there is a usecase for this too, for the amateur TV hobbyist. Might require to write a special kernel-driver which has the benefit of speed and Demux-filters readily available. Also might need a special firmware written for the cx24116 instead of the standard "dvb-fe-cx24116.fw". Add issues/suggestions in the "issue-sction". enjoy, xenpac;)