Category | hvr-1800

Well, that was painful. After a full day working with the various cards, I managed to get all of them working. A couple of caveats: The analog tuner on the HVR-1250 isn't supported yet. The composite and s-video inputs are working but the mt2131 driver doesn't have the required support for tuning to analog stations. The analog tuner is supported though on the HVR-1255, 1800 (both retail and OEM), 1850, etc. (since it's a different chip) While ALSA audio when doing raw capture *is* working, it doesn't seem to work with tvtime for some reason (I added the original ALSA capture support...

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Ever wonder why it's so common for somebody to check in a change to make some new product work, causing a regression in the tuner that *you* have? Well, here's why: All these boards use the exact same driver, despite the fact that they have different core chips and only some of them have an onboard MPEG encoder. To make matters worse, look at all the different input types: Even getting all the equipment together to do the testing is a PITA. I spent twenty minutes digging through boxes for a RCA L/R audio to 1/8" audio converter. It's trivial to accidentally make a change which...

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Spent this evening digging into how the 0x418, 0x419, 0x420, and 0x421 registers are getting the values which cause video corruption. Just as a sanity check I dropped in the HVR-1850 that Steven was kind enough to loan me, and confirmed that the problem doesn't occur there. This also allowed me to dump out the register state for the 1850 board? Why is this useful? Because there were two likely possibilities as to why the 1800 was broken and the 1850 worked: The code path in the driver that initializes the HVR-1800 is somehow different, resulting in the register state being programmed...

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When we last left off, we had reproduced the basic behavior that users reported, using the stock command line tools such as v4l2-ctl and "mplayer /dev/video1". Now we'll talk a bit about the debugging process. To give some context, let's look at a quick diagram showing the various parts of the device: (click to enlarge) For starters, let's now look at what the actual user sees after running the following commands: v4l2-ctl -d 1 -f 62.25 --set-fmt-video=width=720,height=480,pixelformat=mpeg mplayer /dev/video1 The video feed itself is a set of colorbars, a well known reference...

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As a result of numerous users reporting that their HVR-1800 didn't work in analog mode, I finally got some time tonight to dig into the situation. If you don't care about the details, the short answer is I'm working on it and be patient. If you want to get some insight into the gory debugging process, keep reading... Over the next few blog posts, I'll be walking through the typical debugging process. I don't actually know what the actual problem(s) are at this point, so this is a chance for those of you at home to play along. Here's what we do know: Users have reported a variety of different...

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After quite some time of talking about it, we finally got around to getting the analog support for the HVR-1850 submitted upstream. Support for all things analog is present and tested on all the various input types: the MPEG encoder, raw capture, analog audio. This patch series also includes a fix for a long-standing regression in the HVR-1800 as well. http://git.kernellabs.com/?p=stoth/cx23885-hvr1850-fixups.git Users are free to try it building from the above git tree, or they can wait a few days for it to be merged into the upstream linux-media tree. The HVR-1850 is a really nice...

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Been a few days since I've posted an update. Here's a brief summary of things that have been going on in the last week: Progress continued on improving em28xx analog quality. I isolated a problem with chroma AGC in the saa7115, and am working on a fix now. I nailed down most of the analog problems being reported against the HVR-950q under MythTV. Posted a tree with fixes and solicited testers to try it out before submitting it upstream. I finally plugged in my HVR-1800 and took a quick look at the analog support situation under MythTV. It falls down pretty hard with the current v4l-dvb...

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So way back at the end of September, just after the Plumbers Conference 2009 I mentioned on the blog that we were taking another look at the HVR1800 raw audio and VBI support. Well it took a little longer than expected but yesterday we posted a cx23885-audio tree that contains two sets of important changes. 1. It adds support for ALSA audio, applications that understand ALSA can now stream raw analog audio as well as raw analog video. (Remember that TVTime itself does NOT support ALSA directly. See Below). If you're into recording TV audio then you'll be happy about this. 2. It adds support...

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Things are ticking along nicely here at KernelLabs. The Linux Plumbers Conference 2009 took up most of last week and aside from my posting replies here in the blog threads it feels like I haven't posted here in a very long time. So what's new you ask? From my perspective I took a look at Andy Wall's HVR1850 patches over the weekend. Saturday was spent a regression testing those against the HVR1800. Aside from a minor hiccup requiring a new hardware detection patch I think the IR patches are in good shape. As always, we'll know more as the testing expands. Kudos to Andy for running with the IR project. I...

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