xref: /linux/Documentation/admin-guide/media/avermedia.rst (revision a1c3be890440a1769ed6f822376a3e3ab0d42994)
1.. SPDX-License-Identifier: GPL-2.0
2
3======================================
4Avermedia DVB-T on BT878 Release Notes
5======================================
6
7February 14th 2006
8
9.. note::
10
11   Several other Avermedia devices are supported. For a more
12   broader and updated content about that, please check:
13
14   https://linuxtv.org/wiki/index.php/AVerMedia
15
16The Avermedia DVB-T
17~~~~~~~~~~~~~~~~~~~
18
19The Avermedia DVB-T is a budget PCI DVB card. It has 3 inputs:
20
21* RF Tuner Input
22* Composite Video Input (RCA Jack)
23* SVIDEO Input (Mini-DIN)
24
25The  RF  Tuner  Input  is the input to the tuner module of the
26card.  The  Tuner  is  otherwise known as the "Frontend" . The
27Frontend of the Avermedia DVB-T is a Microtune 7202D. A timely
28post  to  the  linux-dvb  mailing  list  ascertained  that the
29Microtune  7202D  is  supported  by the sp887x driver which is
30found in the dvb-hw CVS module.
31
32The  DVB-T card is based around the BT878 chip which is a very
33common multimedia bridge and often found on Analogue TV cards.
34There is no on-board MPEG2 decoder, which means that all MPEG2
35decoding  must  be done in software, or if you have one, on an
36MPEG2 hardware decoding card or chipset.
37
38
39Getting the card going
40~~~~~~~~~~~~~~~~~~~~~~
41
42At  this  stage,  it  has  not  been  able  to  ascertain  the
43functionality  of the remaining device nodes in respect of the
44Avermedia  DVBT.  However,  full  functionality  in respect of
45tuning,  receiving  and  supplying  the  MPEG2  data stream is
46possible  with the currently available versions of the driver.
47It  may be possible that additional functionality is available
48from  the  card  (i.e.  viewing the additional analogue inputs
49that  the card presents), but this has not been tested yet. If
50I get around to this, I'll update the document with whatever I
51find.
52
53To  power  up  the  card,  load  the  following modules in the
54following order:
55
56* modprobe bttv (normally loaded automatically)
57* modprobe dvb-bt8xx (or place dvb-bt8xx in /etc/modules)
58
59Insertion  of  these  modules  into  the  running  kernel will
60activate the appropriate DVB device nodes. It is then possible
61to start accessing the card with utilities such as scan, tzap,
62dvbstream etc.
63
64The frontend module sp887x.o, requires an external   firmware.
65Please use  the  command "get_dvb_firmware sp887x" to download
66it. Then copy it to /usr/lib/hotplug/firmware or /lib/firmware/
67(depending on configuration of firmware hotplug).
68
69Known Limitations
70~~~~~~~~~~~~~~~~~
71
72At  present  I can say with confidence that the frontend tunes
73via /dev/dvb/adapter{x}/frontend0 and supplies an MPEG2 stream
74via   /dev/dvb/adapter{x}/dvr0.   I   have   not   tested  the
75functionality  of any other part of the card yet. I will do so
76over time and update this document.
77
78There  are some limitations in the i2c layer due to a returned
79error message inconsistency. Although this generates errors in
80dmesg  and  the  system logs, it does not appear to affect the
81ability of the frontend to function correctly.
82
83Further Update
84~~~~~~~~~~~~~~
85
86dvbstream  and  VideoLAN  Client on windows works a treat with
87DVB,  in  fact  this  is  currently  serving as my main way of
88viewing  DVB-T  at  the  moment.  Additionally, VLC is happily
89decoding  HDTV  signals,  although  the PC is dropping the odd
90frame here and there - I assume due to processing capability -
91as all the decoding is being done under windows in software.
92
93Many  thanks to Nigel Pearson for the updates to this document
94since the recent revision of the driver.
95