To further this statement for those of you who saw the 411 they demo'd @ Team Summit last week, The visible design of the housing unit did somewhat look similar to the 942. 942 just larger because of it's hard drive and added dvr componentsTech27 said:
Has any news leaked about the future MPEG4 recievers?
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After yakking with my colleagues and checking on the internet, I found some interesting info. There is a lot of MPEG4 IP available, some even as direct loadable VHDL for Xilinx and others.
BTW, the tuner card doesn't have to change, assuming the transport multiplexing hasn't changed (and I wouldn't think it does).
The decoders only enter into the picture when playing video back, they are part of the output stage, not the input stage. When recording the transport is demultiplexed, but not decoded! The raw data is written to disk.
If Dish has chosen to make the 942 upgradable, they could have chosen several paths.
1) Use a software upgradable component like an FPGA. See Hitachi HD64404 of an SD version of such an ASIC. Or a generic Xilinx part may be chosen as well.
2) Place the decoder ASIC/ASICs on a daughter card. Several manufacturers have ASICs that are pin and command compatible with their MPEG2 predecessor ASIC. The MPEG4 stage can be enabled via new commands. Note that there IS NOT DIFFERENCE IN THE INTERFACE from an electrical standpoint between MPEG2 and MPEG4. The bandwidths are the same or less for MPEG4 than for MPEG2.
3) Custom ASIC using IP cores from elsewhere. If Dish is doing it's own ASIC, it may contain an MPEG4/H264 core already. I would believe the lower cost receivers (SD) use an integrated ASIC that provides transport demultiplexing and decoding in one ASIC. The frame buffer on SD is small enough that it can be incorporated into the ASIC, this may not be true for HD because of the somewhat larger frame size.
Other things to note: The 6000 receiver most likely had a separate demultiplexer and decoder. The firewire tap would be after the demultiplexer and before the decoder. This type of decoder is probably a streaming type (most modern decoders can handle data stream or DMA style interfaces).
The 811 is probably integral. The demultiplexer and decoder are in a single ASIC. It most likely doesn't offer any tap for firewire interface.
The 942 is not integral. The demultiplexed stream is written to disk. The disk stream is decoded. Note that the term stream is used loosely here, it's probably actually a DMA based design (disk interfaces are usually DMA).
BTW, the tuner card doesn't have to change, assuming the transport multiplexing hasn't changed (and I wouldn't think it does).
The decoders only enter into the picture when playing video back, they are part of the output stage, not the input stage. When recording the transport is demultiplexed, but not decoded! The raw data is written to disk.
If Dish has chosen to make the 942 upgradable, they could have chosen several paths.
1) Use a software upgradable component like an FPGA. See Hitachi HD64404 of an SD version of such an ASIC. Or a generic Xilinx part may be chosen as well.
2) Place the decoder ASIC/ASICs on a daughter card. Several manufacturers have ASICs that are pin and command compatible with their MPEG2 predecessor ASIC. The MPEG4 stage can be enabled via new commands. Note that there IS NOT DIFFERENCE IN THE INTERFACE from an electrical standpoint between MPEG2 and MPEG4. The bandwidths are the same or less for MPEG4 than for MPEG2.
3) Custom ASIC using IP cores from elsewhere. If Dish is doing it's own ASIC, it may contain an MPEG4/H264 core already. I would believe the lower cost receivers (SD) use an integrated ASIC that provides transport demultiplexing and decoding in one ASIC. The frame buffer on SD is small enough that it can be incorporated into the ASIC, this may not be true for HD because of the somewhat larger frame size.
Other things to note: The 6000 receiver most likely had a separate demultiplexer and decoder. The firewire tap would be after the demultiplexer and before the decoder. This type of decoder is probably a streaming type (most modern decoders can handle data stream or DMA style interfaces).
The 811 is probably integral. The demultiplexer and decoder are in a single ASIC. It most likely doesn't offer any tap for firewire interface.
The 942 is not integral. The demultiplexed stream is written to disk. The disk stream is decoded. Note that the term stream is used loosely here, it's probably actually a DMA based design (disk interfaces are usually DMA).
jpetersohn said:
I don't know that I would agree with this. Most likely the data is decrypted/demuxed/decoded by a single chip. Recordings are stored on disk encrypted (I believe).
HookedOnTV said:
The stream has to be demultiplexed. It isn't going to write the entire TP worth of data to the disk. The decryption is probably part of the decoder stage (i.e. yes, the data would be stored encrypted on the disk).
I have not opened my 942 yet
Any one ever check in side the 921 or 942 for any upgrade slots or sockets.
I cant believe dish would miss such and easy design option for upgrades.
I would look like a slot for a new Mpeg4 daughter board or maybe a new socket for a new Mpeg4 chip or something?
Can any of the chips even be removed? Are they all soldered in or are some in sockets??
I know in the past they had slots on those old HDTV 6000 for new daughter cards so I would think they would do it again thinking of the future.
Just an idea . . .
Any one ever check in side the 921 or 942 for any upgrade slots or sockets.
I cant believe dish would miss such and easy design option for upgrades.
I would look like a slot for a new Mpeg4 daughter board or maybe a new socket for a new Mpeg4 chip or something?
Can any of the chips even be removed? Are they all soldered in or are some in sockets??
I know in the past they had slots on those old HDTV 6000 for new daughter cards so I would think they would do it again thinking of the future.
Just an idea . . .
ScottChez said:
I haven't opened mine either (it's leased, so I'm not going to). If some intrepid soul would post high resolution photos of the circuit board I could probably learn more.
The ASICs are usually SMTs of SOIC, PLCC, TSSOP or QLFC type.
Edit: PLCC is actually a socket type. BGA is what I meant.
Here are some photos of the inside of my 942.
http://www.satelliteguys.us/showpost.php?p=422105&postcount=66
And here is a photo of the insides of a 411 MPEG 411 Receiver
http://www.satelliteguys.us/attachment.php?attachmentid=4050
http://www.satelliteguys.us/showpost.php?p=422105&postcount=66
And here is a photo of the insides of a 411 MPEG 411 Receiver
http://www.satelliteguys.us/attachment.php?attachmentid=4050
Thanks! I have lots of answers for you now:
The 942:
Uses the Broadcom 7038 Dual HD video-on-a-chip system. This consists of the 7038 processor which contains the CPU (300 MHz MIPS R5000 core), a DRAM controller, two MPEG2 video stream decoders, DVB smart card authentication system, audio decoders and auxillary cruft. The transport demultiplexing is provided by Broadcom 4500 DVB satellite tuners (2). 8VSB is provided by a Broadcom 3520 OTA tuner which also has analog capability. The 4500 and 3520 provide demuxed encrypted MPEG data streams to the 7038 which decodes them and/or feeds them to a disk interface for storage. The MIPS R5000 core serves as general purpose
CPU which directs the data flow (but does not handle the data itself).
The demoed MPEG4 box:
The same as above, but only one 4500 and 3520. It also contains (most important) and add-on chip that interfaces with the 7038, namely the Broadcom 7411 AVC/MPEG high definition decoder.
From the pictures of the 942 motherboard I do not see any means of attaching a 7411, although the control interface isn't really complicated. It can be hooked up with a generic 16-bit bus, PCI, SPI or GPIO interfaces.
Is there a picture of the hidden portion of the mainboard in the 942?
The 942:
Uses the Broadcom 7038 Dual HD video-on-a-chip system. This consists of the 7038 processor which contains the CPU (300 MHz MIPS R5000 core), a DRAM controller, two MPEG2 video stream decoders, DVB smart card authentication system, audio decoders and auxillary cruft. The transport demultiplexing is provided by Broadcom 4500 DVB satellite tuners (2). 8VSB is provided by a Broadcom 3520 OTA tuner which also has analog capability. The 4500 and 3520 provide demuxed encrypted MPEG data streams to the 7038 which decodes them and/or feeds them to a disk interface for storage. The MIPS R5000 core serves as general purpose
CPU which directs the data flow (but does not handle the data itself).
The demoed MPEG4 box:
The same as above, but only one 4500 and 3520. It also contains (most important) and add-on chip that interfaces with the 7038, namely the Broadcom 7411 AVC/MPEG high definition decoder.
From the pictures of the 942 motherboard I do not see any means of attaching a 7411, although the control interface isn't really complicated. It can be hooked up with a generic 16-bit bus, PCI, SPI or GPIO interfaces.
Is there a picture of the hidden portion of the mainboard in the 942?
Scott Greczkowski said:No I did not take apart that portion of te 942, did not want to void my warranty.
The secret may lurk beneath the power supply board.
ScottChez said:
The 921 could be upgraded as it has the space and needed slots for additional cards. The 942 does not.
Paradox-SJ said:
Not necessarily. The daughtercard for a 7411 wouldn't need to be all that big. I really would like to see a complete picture (without hidden sections) of the 942 system board.
I don't know the internals of the 921, but I would venture a guess that the daughter cards held the analog portions of the tuner and the demux, but not the stream decoder.
I am surprised the HDD is a SATA drive. Just because regular ATA drives are selling for quite a bit less still. Props to E* for that.
CWS_kahuna said:
The Broadcom 7038 does not feature an onboard ATA interface. I suspect this was done for pin count reasons. SATA requires a lot fewer pins than ATA.
I suspect that Dish could have an upgrade for the 942 to MPEG-4 if they want to do so. It would probably involve you shipping in your 942 to have a new main board put in it. The powersupply, case, disk all remains the same.
I am sure Dish will investigate what is the cheapest way to do the upgrade. Perhaps it is cheaper to just send out new boxes than to try to upgrade the old ones.
I am sure Dish will investigate what is the cheapest way to do the upgrade. Perhaps it is cheaper to just send out new boxes than to try to upgrade the old ones.
Tech27 said:Very interesting thread although a lot of it's content is way over my head!! We'll all be chomping at the bit on this one till there is an official anouncement from E*. Assuming what they anounce is what they actually plan to do!!
Only thing Echostar has really "announced" is that one day all the receivers will need to be upgraded to MPEG-4. When/how that will happen has not been announced. Reports from the Dish summit meeting showed prototypes of the new receivers (look for the 411 receiver thread). I suppose they are still working the bugs out and then once they have a box that works they will announce the changeover plans.
