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