Category | demods

After a rather large bug hunt, I've finally submitted the HVR-950q patches upstream. In the end, we created 24 patches addressing a ton of longstanding bugs: au8522: fix intermittent lockup of analog video decoder au8522: Fix off-by-one in SNR table for QAM256 au8522: properly recover from the au8522 delivering misaligned TS streams au0828: Make the s_reg and g_reg advanced debug calls work against the bridge xc5000: properly show quality register values xc5000: add support for showing the SNR and gain in the debug output xc5000: properly report i2c write failures au0828:...

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Continued debugging has produced another dozen fixes for the HVR-950q. Most of these are low-probability failure conditions (race conditions, etc). However take a bunch of 1/1000 chance items together and you're likely to hit one of them once in a while... A couple of noteworthy changes: Firmware load time has been sped up to 2.9 seconds (down from 8-10 seconds). This should eliminate the need for MythTV users to specify the "no_poweoff" xc5000 modprobe since it will now load fast enough to avoid a mythfrontend timeout. Fix a case where the xc5000 tuner enters a failure state and all subsequent...

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As of the release of Linux Kernel 3.1, Hauppauge's WinTV-Aero-m is fully supported for use with both ATSC and DVB-T, using the new MFE framework within dvb-usb to represent two frontends on a single DVB adapter. This makes the Aero-m the first semi-worldwide terrestrial digital television broadcast receiver to be supported under Linux. The device is built of two LG broadcast demodulators and a MaxLinear SoC. The first LG demodulator, LG DT3305, has been well supported in Linux for ATSC ever since I released it a few years ago. I've written a new driver to support the other LG demodulator,...

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It's been a while since we've had a blog post, so I figured it would be a good time for an update as to some things going on. We're continuing to work in a number of areas, although in some cases things are moving along "behind the scenes" and are less visible to the public. First, let's talk about the HVR-950q.... As a result of some consulting we did in the last month, I spent *alot* of time digging into the tuning behavior for the HVR-950q. This included finding several bugs which explain some of the "sometimes tuning just fails" type behavior. These are the sorts of things that only...

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I'm pleased to announce the mxl111sf Linux driver with support for ATSC on the Hauppauge WinTV-Aero-m. The device uses a Max Linear tuner with the LG DT3305 ATSC/QAM demodulator. The device also supports ATSC-MH Mobile DTV, but that feature is not yet supported under Linux. Since I began work on this driver over a year and a half ago, mercurial was the tool used to track development. If you are the owner of one of these USB dongles, please feel free to give the following repository a try: http://kernellabs.com/hg/~mkrufky/mxl111sf Please note, the mxl111sf mercurial development...

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After sitting in a public KernelLabs tree for almost 13 months, I finally got around to merging the Micronas DRX-D driver upstream, so now DVB support for the PCTV 330e and HVR-900 R2 are in the upstream kernel (for 2.6.40). So if you've been using the KernelLabs HG tree (which required considerable modification to work with recent kernels), it is no longer an issue and you should either wait for 2.6.40 to be released or use the main LinuxTV media_build tree as opposed to the tree hosted on KernelLabs. Instructions for installing the LinuxTV media_build tree can be found in the LinuxTV wiki. Thanks...

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On this fine Independence Day, the PCTV 80e declares independence from the tyranny of Windows. Ok, apologies to anyone from the U.K. for my quirky American sense of humor. Seriously though, Trident Microsystems finally agreed to allow the DRX-J code to be released under a BSD license. This means that we can finally release a driver for the PCTV 80e. http://www.kernellabs.com/hg/~dheitmueller/v4l-dvb-80e The ATSC support has been tested. Haven't had a chance to burn in the ClearQAM support. And there's a bunch of cleanup work required before it can be submitted upstream. But it does...

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I finally found a few hours to sit down and debug the issue people were reporting where switching back and forth between analog and digital modes under MythTV would intermittently fail with the hvr-950q. It turns up there were a couple of race conditions related to the power management of the chip. http://kernellabs.com/hg/~dheitmueller/hvr-950q-pmfixes/ There was also a neat bug where the first tuning request after switching from analog mode back to digital would *always* get dropped on the floor. This would cause users to see the first tuning request fail, or there would be cases where...

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Over the last few nights, I finally got a MythTV box setup that I could use for some testing of the HVR-950q. I did some work a few months ago to basically get the analog support working, but there were some reports of problems related to switching back and forth between analog and digital mode. After adding some debugging to the driver, I found basically three classes of problems: 1. The power management on the au8522 was setup such that the chip would get completely powered down when switching modes. Essentially what would happen is when switching from analog to digital mode, the v4l stack...

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While Steven continues to churn away on ALSA audio and VBI support for the HVR-1800, I have started working on a project to do ALSA audio for the HVR-1600. So if you have an interest in being able to use the raw analog video capabilities for the 1600, stay tuned! The call for testers for the ClearQAM fixes has been very successful, and I am happy to report that 100% of the people who have done testing have seen a significant improvement in ClearQAM performance, with none reporting a regression. That said, I will be issuing a PULL request this weekend to get the changes into the mainline v4l-dvb...

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