DVB via USB
For information about supported devices, see an article under the appropriate device category (e.g. DVB-T, ATSC,...) and then classification (USB) section. For USB:
* DVB-T USB Devices * DVB-C USB Devices * DVB-S USB Devices * ATSC USB Devices * Work-in-progress and new USB Devices Please help to keep these lists up-to-date so that they are useful for everyone!
Here is an (non-exhaustive) overview of DVB/ATSC USB devices. Generally, when it comes to support for USB devices, it is a good idea to try the current Hg sources because some device drivers can be very new and thus may have not made their way into the mainstream kernel.
For all devices shown below you need to load (if not compiled into the kernel):
- i2c-core - crc32 - firmware_class - dvb-core.ko - dvb-pll.ko
and maybe others too. If the loading fails for any particular module you'll get a "unknown symbol" message. Then have a look at dmesg to find out, which symbols (functions) are missing. After you've found out which module was absent, please come back here and add it to the list/device-entry.
The Type field specifies the USB standard(s) supported by the device.
- The device supports USB 1.1 only, and will work at 1.1 speeds when attached to a USB 2.0 port.
- The device supports USB 2.0 only, and will not work when attached to a USB 1.1-only port. Such devices are normally capable of delivering the complete Transport Stream to the software demuxer.
- USB2.0, USB1.1
- The device supports USB 1.1 and USB 2.0, and will work at any speed supported by 1.1 or 2.0. When running in USB 2.0 mode, such devices can deliver the complete Transport Stream (unless specified otherwise).
You need to copy the firmware to the correct place on your system. This will normally be /lib/firmware or a folder below it. Here is an example:
- $ cd /lib/firmware - $ ls - 2.6.15-23-amd64-xeon - $ cd 2.6.15-23-amd64-xeon - $ sudo cp ~/dvb-usb-umt-010-02.fw .
Now, you need to unplug your USB device. Plug it in again, and then take a look at dmesg.
- $ dmesg - < ...... lines cut for clarity ..... > - usb 5-2: USB disconnect, address 3 - usb 5-2: new high speed USB device using ehci_hcd and address 8 - dvb-usb: found a 'Hanftek UMT-010 DVB-T USB2.0' in cold state, will try to load a firmware - dvb-usb: downloading firmware from file 'dvb-usb-umt-010-02.fw' to the 'Cypress FX2' - dvb-usb: Hanftek UMT-010 DVB-T USB2.0 successfully initialized and connected. - usb 5-2: USB disconnect, address 8 - dvb-usb: generic DVB-USB module successfully deinitialized and disconnected.
In this case, I have success, because the firmware was loaded.
Additional technical information
This section starts describing devices which hit the market beginning of spring 2004. It does not cover TTUSB-based devices.
DVB-USB devices host-controlled
When first AC-Adapter-free USB devices (with the capability of receiving DVB Signals) hit the market, every vendor was using the generic USB-device-controller from Cypress (FX1 (AN2135/AN2235), FX2) as an interface between the DVB-hardware and the host.
As those controllers are very generic, one has to create (and download) an (small or not so small) embedded software to those controller to give vendor-specific and the wanted functionality. After downloading the so-called firmware vendors used the reboot-feature of the controller to re-enumerate with new USB Vendor/Product-IDs and a new USB-layout. On the host this looks like a normal disconnect and connect of an USB device.
Because the memory for storing the firmware was limited, vendors decided not to put any DVB-demodulator and RF-tuner specific code into the firmware, but only to implement interface functionality. At that time, the common way to control other components was I2C. The other necessary feature was data-streaming. With such a firmware, every functionality is done from the host - mainly the driving of the demodulator and the tuner.
Host-controlled devices are the ones based on DiBcom (dibusb, dib0700), Nebula (DigiTV), Hanftek and others. (see below)
DVB-USB device firmware-controlled
Another approach was coming later: When it started, that putting more memory on a board/into an IC with almost no increase of the BOM. Vendors started to put the demodulator and tuner-driver into the firmware. This was simplifying the host-part dramatically, because if you have a new hardware, you just need to modify the (platform-independent) firmware part and, as long as the firmware-interface is not changing, the host-driver stays the same.
Firmware-controlled devices: Twinhan VP7045/VP7021, Terratec Cinergy T2, Wideview and others.