Hi Andy - I really appreciate this reply! Very helpful.
I did find a datasheet via Google for the CX23416 which had pinouts and stuff, though it made no mention of loading firmware and stuff. I gather that this datasheet is supposed to be locked up tight though and maybe isn't supposed to be publicly downloadable - is it just as restrictive for the CX23417 and CX23418? I would love to see datasheets for either of those two. Thanks, Ben On Sat, Apr 11, 2009 at 11:58 PM, Andy Walls <[email protected]> wrote: > On Sat, 2009-04-11 at 17:17 -0400, Ben Gelb wrote: >> Perhaps this isn't the perfect forum for this question since its not >> really a software question, but I can't really think of any other. So >> sorry in advance if people find this to be "off topic." >> >> I'm interested in accessing the "encoded stream output interface" on >> the CX23416 (not the MCU/PCI interface!) and using it to drive some >> other digital logic (homebrew DVB-S transmitter). >> >> >From the CX23416 datasheet, it looks like I can just stream a TS out >> of this output port. > > AFAIK, the CX23416 firmware does not produce a TS; just a PS, an MPEG 1 > Stream, or PES's of various types. > > I'm unsure about the CX23417's ability to produce a TS (I doubt it), but > it certainly has an output port of some sort, as it doesn't have a PCI > interface. > > I know that the CX23418 firmware can produce a TS; the Linux cx18 driver > can tell the chip to do just that. The publicly available datasheet > also says that MPEG output can be supported on a 1-bit serial peripheral > interface. (Note, the linux cx18 driver doesn't configure that output > port; the driver only sets up MPEG streams to come the PCI bus.) > > > >> Does anybody know if this port is physically accessible on any of the >> common capture cards? > > I have no idea. > > The ones you'd have the best shot at are cards with a CX23417. That > chip doesn't have a PCI interface. It has to clock the MPEG stream out > to a PCI bridge chip, so the MPEG stream should be accessable. Of > course, I have no idea if the CX23417 produces an MPEG TS. You'll have > to check the linux drivers that actually support boards with that chip > to try and get an idea. > > >> It's a bit unfortunate that the CX23416 is a BGA >> package, since it makes it hard (not really possible) to tack on >> wires. > > Also the pinouts aren't publicly available. > > >> Any helpful suggestions appreciated. > > 1. If this is a one-off project, I'd just use a CX23418 based card to > capture an MPEG TS. Then I'd use a homebrew piece of hardware to shift > it out a serial or parallel interface. You're going to have to stuff > the TS with NULL packets to get proper DVB-S rate adaptation correct > anyway (right?). (BTW who's transponder are you going to use? ;) ) > > With that, I think you'll spend less time on guessing at software > commands to get the output port configured and started, and also less > time guessing at pins and frying boards. > > > > 2. If this is a serious project into which you'd like to invest a > non-trivial amount of $, then contact your regional Conexant sales rep. > > > > Unless you get lucky figuring out the pins on a board with a CX23417, > anything other than 1 or 2 above is likely to be frustrating, and may > consume a lot of time and effort in the process. > > Regards, > Andy > > >> Thanks, >> Ben > > > > _______________________________________________ > ivtv-devel mailing list > [email protected] > http://ivtvdriver.org/mailman/listinfo/ivtv-devel > _______________________________________________ ivtv-devel mailing list [email protected] http://ivtvdriver.org/mailman/listinfo/ivtv-devel
