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3.4 KiB
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95 lines
3.4 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
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======================================
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Avermedia DVB-T on BT878 Release Notes
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======================================
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February 14th 2006
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.. note::
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Several other Avermedia devices are supported. For a more
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broader and updated content about that, please check:
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https://linuxtv.org/wiki/index.php/AVerMedia
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The Avermedia DVB-T
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~~~~~~~~~~~~~~~~~~~
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The Avermedia DVB-T is a budget PCI DVB card. It has 3 inputs:
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* RF Tuner Input
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* Composite Video Input (RCA Jack)
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* SVIDEO Input (Mini-DIN)
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The RF Tuner Input is the input to the tuner module of the
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card. The Tuner is otherwise known as the "Frontend" . The
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Frontend of the Avermedia DVB-T is a Microtune 7202D. A timely
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post to the linux-dvb mailing list ascertained that the
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Microtune 7202D is supported by the sp887x driver which is
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found in the dvb-hw CVS module.
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The DVB-T card is based around the BT878 chip which is a very
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common multimedia bridge and often found on Analogue TV cards.
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There is no on-board MPEG2 decoder, which means that all MPEG2
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decoding must be done in software, or if you have one, on an
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MPEG2 hardware decoding card or chipset.
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Getting the card going
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~~~~~~~~~~~~~~~~~~~~~~
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At this stage, it has not been able to ascertain the
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functionality of the remaining device nodes in respect of the
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Avermedia DVBT. However, full functionality in respect of
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tuning, receiving and supplying the MPEG2 data stream is
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possible with the currently available versions of the driver.
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It may be possible that additional functionality is available
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from the card (i.e. viewing the additional analogue inputs
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that the card presents), but this has not been tested yet. If
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I get around to this, I'll update the document with whatever I
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find.
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To power up the card, load the following modules in the
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following order:
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* modprobe bttv (normally loaded automatically)
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* modprobe dvb-bt8xx (or place dvb-bt8xx in /etc/modules)
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Insertion of these modules into the running kernel will
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activate the appropriate DVB device nodes. It is then possible
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to start accessing the card with utilities such as scan, tzap,
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dvbstream etc.
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The frontend module sp887x.o, requires an external firmware.
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Please use the command "get_dvb_firmware sp887x" to download
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it. Then copy it to /usr/lib/hotplug/firmware or /lib/firmware/
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(depending on configuration of firmware hotplug).
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Known Limitations
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~~~~~~~~~~~~~~~~~
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At present I can say with confidence that the frontend tunes
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via /dev/dvb/adapter{x}/frontend0 and supplies an MPEG2 stream
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via /dev/dvb/adapter{x}/dvr0. I have not tested the
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functionality of any other part of the card yet. I will do so
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over time and update this document.
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There are some limitations in the i2c layer due to a returned
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error message inconsistency. Although this generates errors in
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dmesg and the system logs, it does not appear to affect the
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ability of the frontend to function correctly.
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Further Update
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~~~~~~~~~~~~~~
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dvbstream and VideoLAN Client on windows works a treat with
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DVB, in fact this is currently serving as my main way of
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viewing DVB-T at the moment. Additionally, VLC is happily
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decoding HDTV signals, although the PC is dropping the odd
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frame here and there - I assume due to processing capability -
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as all the decoding is being done under windows in software.
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Many thanks to Nigel Pearson for the updates to this document
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since the recent revision of the driver.
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