0001 .. SPDX-License-Identifier: GPL-2.0
0002
0003 ======================================
0004 Avermedia DVB-T on BT878 Release Notes
0005 ======================================
0006
0007 February 14th 2006
0008
0009 .. note::
0010
0011 Several other Avermedia devices are supported. For a more
0012 broader and updated content about that, please check:
0013
0014 https://linuxtv.org/wiki/index.php/AVerMedia
0015
0016 The Avermedia DVB-T
0017 ~~~~~~~~~~~~~~~~~~~
0018
0019 The Avermedia DVB-T is a budget PCI DVB card. It has 3 inputs:
0020
0021 * RF Tuner Input
0022 * Composite Video Input (RCA Jack)
0023 * SVIDEO Input (Mini-DIN)
0024
0025 The RF Tuner Input is the input to the tuner module of the
0026 card. The Tuner is otherwise known as the "Frontend" . The
0027 Frontend of the Avermedia DVB-T is a Microtune 7202D. A timely
0028 post to the linux-dvb mailing list ascertained that the
0029 Microtune 7202D is supported by the sp887x driver which is
0030 found in the dvb-hw CVS module.
0031
0032 The DVB-T card is based around the BT878 chip which is a very
0033 common multimedia bridge and often found on Analogue TV cards.
0034 There is no on-board MPEG2 decoder, which means that all MPEG2
0035 decoding must be done in software, or if you have one, on an
0036 MPEG2 hardware decoding card or chipset.
0037
0038
0039 Getting the card going
0040 ~~~~~~~~~~~~~~~~~~~~~~
0041
0042 At this stage, it has not been able to ascertain the
0043 functionality of the remaining device nodes in respect of the
0044 Avermedia DVBT. However, full functionality in respect of
0045 tuning, receiving and supplying the MPEG2 data stream is
0046 possible with the currently available versions of the driver.
0047 It may be possible that additional functionality is available
0048 from the card (i.e. viewing the additional analogue inputs
0049 that the card presents), but this has not been tested yet. If
0050 I get around to this, I'll update the document with whatever I
0051 find.
0052
0053 To power up the card, load the following modules in the
0054 following order:
0055
0056 * modprobe bttv (normally loaded automatically)
0057 * modprobe dvb-bt8xx (or place dvb-bt8xx in /etc/modules)
0058
0059 Insertion of these modules into the running kernel will
0060 activate the appropriate DVB device nodes. It is then possible
0061 to start accessing the card with utilities such as scan, tzap,
0062 dvbstream etc.
0063
0064 The frontend module sp887x.o, requires an external firmware.
0065 Please use the command "get_dvb_firmware sp887x" to download
0066 it. Then copy it to /usr/lib/hotplug/firmware or /lib/firmware/
0067 (depending on configuration of firmware hotplug).
0068
0069 Known Limitations
0070 ~~~~~~~~~~~~~~~~~
0071
0072 At present I can say with confidence that the frontend tunes
0073 via /dev/dvb/adapter{x}/frontend0 and supplies an MPEG2 stream
0074 via /dev/dvb/adapter{x}/dvr0. I have not tested the
0075 functionality of any other part of the card yet. I will do so
0076 over time and update this document.
0077
0078 There are some limitations in the i2c layer due to a returned
0079 error message inconsistency. Although this generates errors in
0080 dmesg and the system logs, it does not appear to affect the
0081 ability of the frontend to function correctly.
0082
0083 Further Update
0084 ~~~~~~~~~~~~~~
0085
0086 dvbstream and VideoLAN Client on windows works a treat with
0087 DVB, in fact this is currently serving as my main way of
0088 viewing DVB-T at the moment. Additionally, VLC is happily
0089 decoding HDTV signals, although the PC is dropping the odd
0090 frame here and there - I assume due to processing capability -
0091 as all the decoding is being done under windows in software.
0092
0093 Many thanks to Nigel Pearson for the updates to this document
0094 since the recent revision of the driver.
