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I tried doing

   chmod u+s /usr/bin/mythbackend /usr/bin/mythfrontend

to see if it would make the display of the show actually work properly. No dice. I wonder now if there’s an issue with the X display properly using the Hauppauge card? I worder if there are hardware options available on the card that my XF86Config should use to make things go more quickly.

Actually, I suspect the first thing I should do is check out the latest ivtv driver. Build it, make it reboot to load it (I’ve not been able to make the module unload, try as I might). One helpful comment from someone suggested that I shouldn’t be forced to do quite the level of custom settings in /etc/mythtv/modules/ivtv as I have been. The newer driver reportedly does a lot of the work for you, so you don’t have to specify which card, PAL vs NTSC (I’m suspect of the chances of this), etc.

Just a matter of time. I’ve got to get this working in the next couple of weeks, or I know the holidays will make me not touch it again until January. That would just be ridiculous. 🙂

Haven’t been able to work on the TV pvr-box much for the last couple of weeks. Hopefully this coming weekend I’ll be able to attack it with furvor. I want to fix sound, and get all of the channels going. A friend sent me their MythTV channels list, in the great form of SQL commands. That means I’ll just have to do a bit of editing, and I can recreate the appropriate databasese in MySQL to let it have everything it should need.

My friend Declan and I messed with it a bit last week and I was able to make a single channel show up properly. Well, that’s not exactly right. The picture is skipping frames a lot. I got an AMD Sempron 2600+ 1.833 GHz CPU for this, which I thought would be plenty for what it’ll be doing. But I’m suddenly suspicious that in my efforts to be frugal, I undercut the ability to make the box work properly.

The rest of the hardware in this is:

• Shuttle SN45GV2 Barebone PC box (I love this thing now and want more of them 🙂 )
• 512Mb of Corsair Value S. PC3200 DDR-DIMM memory
• nVidia-based GeForce2 GTS video card with 64Mb of video RAM
• Maxtor 250GB Internal Hard Drive, 7200 RPM
• Hauppauge WinTV PVR 350 Personal Video Recorder PCI card
• external Linksys WET54G Wireless-G Ethernet Bridge, version2 (whatever that means)
• random CD-ROM I had lying around in our attic (you don’t want to know the volume of junk up in that attic…

Cross your fingers that nothing will eat up the time on Saturday or Sunday.

On an impulse, this morning I switched the input line into the tv-box. I plugged the tv-box’s input line to instead go into the TV, to see just what the tv-box has been getting. Messy, snowy, though not quite as severe as was appearing on the tv-box. That’s from using the wall plug for NTL basic cable apparently. (I wonder if the tv-box itself is emitting enough distortion to cause it?)

There’s also a coax cable coming from a separate box on the wall for NTL digital cable. That line goes to a small splitter where the guy who installed it made the signal both go to the regular (fly plug it’s called?) plug on the TV, and also to the input on the NTL digital cable box (made by Pace). Fine, I made the tv-box’s cable plug into that little splitter for its input, instead of the wall. Tried the tv-box’s cable now into the TV again, and voila, a nice crisp picture. Hmm.

I put the cable back into the tv-box, so it’s now getting that nice crisp picture as its input. I make the TV show me the S-Video coming from the tv-box. It’s certainly better, though it is still a bit snowy and jerky, and it only shows a channel ‘1’ with no channel title on the bottom of the screen. Something else must be screwed up. I ran mythtv-setup again saying ‘yes’ to the question, “Would you like to clear all program/channel settings before starting configuration?” Then again created a new Video Source named “NTL”, choosing “United Kingdom (Alternative)” for its channels. Down to terminal window for adding channels where ps shows me that it ran

	  tv_grab_uk_rt --config-file '/home/mythtv/.mythtv/NTL.xmltv' --configure

But it’s not the happiest; it gave me the prompt

	  Enter the name of a channel, or '.' to finish selecting channels: BBC1
	  Which channel to add?  (I hit Return here)
	  Died at /usr/bin/tv_grab_uk_rt line 257,  line 4.

Maybe a bug? Fine, I’ll get the latest version of the script to see if it fixes the problem of not listing the channels matching your search string, like the previous KnoppMyth-included version did. I have to first install CVS since KnoppMyth doesn’t include it by default: apt-get install cvs. When it asked about location of the repositories, I left the /var/lib/cvs default and on the next screen, chose ‘ignore’ to not worry about not having any. Also told it to not enable the CVS pserver. Great!

Now we can get the file:

	cvs -d:pserver:anonymous@cvs.sourceforge.net:/cvsroot/xmltv login
		(ignoring the warning about .cvspass not existing yet)
	cvs -d:pserver:anonymous@cvs.sourceforge.net:/cvsroot/xmltv co xmltv
	cd xmltv
	perl grab/uk_rt/tv_grab_uk_rt.PL new-uk /usr/share/xmltv
	as root:
	  mv --backup new-uk /usr/bin/tv_grab_uk_rt
	  chmod 755 /usr/bin/tv_grab_uk_rt

Looking at the diff between the versions, I see that the tv_grab_uk_rt script is now calling ask_choice instead of ask about which channel to add. That was the fix so it now properly lists the matches for ‘BBC1’ or ‘RTE1’.

Back into the Channel Editor we go, now add RTE1 again (since we didn’t get past creating the Video Source), added RTE1 using A11 for both the Channel Name and Frequency ID, but on the third screen asking for the frequency in Hz I left that blank, as well as not modifying the subsequent screen. Then re-ran mythfilldatabase. Much more quiet now (a few messages about wide characters for perl’s IO/Handle.pm line 147, but nothing else). For whatever reason, it’s still invoking

	  /usr/bin/perl /usr/bin/tv_grab_uk_rt --days 1 --offset 0
                --config-file /home/mythtv/.mythtv/NTL.xmltv --output /tmp/mythuZ2Jfu

which has me curious since one of the sites yesterday had a comment about making it understand that it’s getting a full two weeks of information in the radiotimes.com output now. Perhaps I need to rebuild mythfilldatabase to make it understand that? Yeesh.

After a while it’s made it to October 21 in getting the program information, but it’s also still giving the

	Duplicate entry '1000-2004-11-03 22:15:00-678-' for key 1

error. Oh well, more tonight maybe.

Heh, this is a blog catagory turning into a ChangeLog.

After some crazy effort, I can now visit the URL

	http://p/program_listing.php

and it correctly lists the shows on tonight on both RTE1 and TV3, the two channels I’ve added. It turns out all attempts to use ‘tv_grab_uk_rt’ as included in the KnoppMyth R4V4 that I installed are going to fail. I came upon notes both on the MythTV Users list and the XMLTV site. It turns out radiotimes.com, the site used by the perl script to get airing information, started to block the User-Agent that the script was using to identifying itself. But they were really cool—instead, the’ve put the information for the next two weeks available in raw XML format.

So I had to download the newer XML 0.5.35 from the XMLTV SourceForge page. I built it by doing

	  tar jxf xmltv-0.5.35.tar.bz2
	  make Makefile.PL
	  make
	  make test          (this does tons of them)
	  make install

Following the examples on those mailing list sites, I ran

	tv_grab_uk_rt --configure

and then invoked

	tv_grab_uk_rt

That seemed to be getting useful information finally, so I invoked my old friend

	mythfilldatabase

but it gave me errors of the form

	Updating icons for sourceid: 1
	Unknown xmltv channel identifier: rte-1.rte.ie
	Skipping channel.
	Unknown xmltv channel identifier: tv3.ie
	Skipping channel.

How odd. Some more reading, and I discovered my mistake—if you look at the channels.dat file that radiotimes.com gives the script, you can see that they’ve changed the format from what it used to offer. Instead of just “231:RTE-1” it now says

	rte-1.rte.ie:231:RTE-1

In the mythtv-setup Channel Editor, I’d thought I was so clever figuring out that I had to put 231 in the ‘XMLTV ID’ field for RTE1. Those identifier errors above helped me realize that it was searching based on the first field in that file, so now the ‘XMLTV ID’ should be the server name, like rte-1.rte.ie for RTE1. Fine, I fixed both RTE1 and TV3.

Some more swimming with Google and I found a discussion talking about exactly this problem. I went into the Channel Editor, and for both RTE1 and TV3 I changed the “Channel Number” and “Frequency ID” entries to be A11 for RTE1 and A9 for TV3 (based on what was in the pal-ireland file I mentioned earlier). The fundamental change being made with this was that my channel number of “1” for RTE1 and “3” for TV3 seem really wrong after reading all of these sites, including this most recent discussion page.

Having the frequency entry in both fields may be correct, but there’s no obvious change yet. I just tried looking at either channel, and they’re both snowy and hard to see. Though I’ll admit the RTE1 channel has more color and movement on it compared to the grey/white mess that was there before. TV3 looks the same as it did.

Wonder what I’m missing? That’s all right—the fact that it’s getting the show information is a big positive step for only a little amount of effort today.

I looked at some of the other stuff the MythWeb interface gives you when you point your browser at the tv-box. Included is MythWeather, which sounds really handy. At the moment, it shows current and upcoming East Irvine CA, including a weather.com radar shot. Wonder if it’s easily changeable? All I’ve found so far is the entry in the /usr/share/mythtv/KnoppMyth.sql file, which has the line

	  INSERT INTO settings VALUES ('locale','USCA0326','MythTVhost');

The “USCA0326” number appears to come out of an entry in /usr/share/mythtv/mythweather/accid.dat. But it’s unclear if it’s possible to change this value in any way other than manually with mysql. Maybe if I upgrade the MythTV software on my system to the 0.16 version released on September 20th, it’ll be as integrated as the release notes suggest and this sort of change would be easy? Another day…

Last night I spent some time wrestling with trying to tune in a channel but no luck. MythTV has a ‘FrequencyID’ part of the channel page under mythtv-setup, but I’ve not yet verified what it’s supposed to be. I tried putting in the frequency for RTE1 that is shown on the NTL Frequency List. That didn’t quite do it. With a little digging, I then discovered /usr/share/xawtv/ and next tried “ptune.pl -f pal-ireland A6“. Almost! It showed a snowy picture of what I later found to be TV3 with a football match (soccer). But it was really hard to see, and more interestingly it was moving in bursts. Like the system couldn’t keep up with it and was dropping frames. Hmm.

Running MythTV by hand as the mythtv user, I saw:

2004-10-19 19:15:07 Running as SUID root would allow some threads to run with realtime priority, improving video smoothness.
***
* Your system is not capable of displaying the
* full framerate at 720x576 resolution.  Frames
* will be skipped in order to keep the audio and
* video in sync.

That’s what makes me suspect both about what’s in /etc/mythtv/modules/ivtv but also if I’m missing a bit in /etc/X11/XF86Config-4

I’m digging around for the efforts of others, including a helpful HowTo about using KnoppMyth with a PAL signal. With some instructions on installing with the Hauppauge PVR-350, I found that by running tveeprom I’m able to get this in /var/log/messages (or dmesg):

Oct 19 20:00:39 p kernel: tvee: Hauppauge: model=48135, rev=J324, serial#=2760998
Oct 19 20:00:39 p kernel: tvee: tuner=Philips FM1246 (idx=24, type=1)
Oct 19 20:00:39 p kernel: tvee: tuner fmt=PAL(I) (eeprom=0x10, v4l2=0x00000010)
Oct 19 20:00:39 p kernel: tvee: audio_processor=CS5331 (type=9)

Ok, that tells me the tuner type.

I also discovered the /etc/init.d/set_ivtv_params script. It will set the various parts of the video device for me if I put the correct values into /etc/sysconfig/ivtv/cfg-0. So that now has the right values of

	IVTV_TUNER='1'
	IVTV_TYPE='PAL'

That choice is backed up by the header /usr/local/lib/ivtv/driver/tuner.h which lists the different tuners, with my choice being

        #define TUNER_PHILIPS_PAL_I 1

That matches the PAL_I sticker on the replacement PVR-350 card that I got the other day. A step closer?

Well, I think so; with some grepping, I discovered /usr/local/lib/ivtv/utils/videodev2.h, which would seem to suggest I honor the value of V4L2_TUNER_ANALOG_TV which is 2. Hmm. Well, for the moment in /etc/mythtv/modules/ivtv I’ll try out

	options tuner type=2 pal=1

but that seems to contradict the suspected value for IVTV_TUNER. Gahh. Time to read more sources I think. There’s lots of good stuff under /usr/local/lib/ivtv.

I’ve put copies of each of these files online so others can see them, and I’ll be keeping them in sync with what’s really being used:

• /etc/X11/XF86Config-4
• /etc/mythtv/modules/ivtv
• /etc/sysconfig/ivtv/cfg-0
• /etc/init.d/set_ivtv_params

(Any suggestions on how to better offer these are welcome.)

Now /etc/mythtv/modules/ivtv contains

	alias char-major-81 videodev
	alias char-major-61 lirc_i2c
	alias char-major-81-0 ivtv
	alias char-major-81-1 bttv
	alias /dev/v4l ivtv
	options ivtv debug=1 ivtv_pal=1
	options tuner type=2 pal=1
	options saa7127 enable_output=1 output_select=1 pal=1
	options msp3400 once=1 simple=1
	add below ivtv msp3400 saa7115 saa7127 tuner
	add above ivtv lirc_dev lirc_i2c ivtv-fb

Anything look really wrong?

I think when I’m all done and have this actually working, I’m going to create my own HowTo combining the efforts of the others, but also including links to example files for everything. And then pitch to have those included in some future release of mythtv. If everybody wants lots of people to be able to use and enjoy this cool stuff, there are still a few things past the great KnoppMyth packaging that have to happen. At least, for anybody who’s not in the US. Wouldn’t it be cool if KnoopMyth let you choose (or even click on) where you live, and have it auto-configure most of the stuff that really doesn’t need to be done manually? And no command-line mythfilldatabase invocation?

Tucked away next to the PVR box (nay, tv-box) is a nice tiny Linksys WET54G wireless bridge. It’s a device that lets anything become part of a wireless network without requiring you to have a wireless card or other antenna. A random PC can become a wireless PC just by plugging it into the bridge, as long as the PC has an Ethernet port. (A lot of motherboards now include at least one Ethernet port by default, as do most laptops.) The bridge talks through the air to the rest of our network, and a tiny Ethernet cable goes from the bridge into the tv-box. My 7-meter Ethernet cable gets to be put away and restore a little order to our livingroom.

There are minor steps companies like Linksys could take to make their products so much more friendly to non-Windows systems. They seem to assume that most customers are putting the bridge onto a Windows network, with a Windows PC. Gah. So I had to search Google to find the bridge’s default address (192.168.1.226) to configure it. I presume the CD that comes with it has it mentioned in the docs somewhere, but it’s still silly that they don’t make some note of it somewhere on the single-sheet install doc in the box. (I just remembered that .226 was the same default address for the similar WET11 bridge over in the states. A silly number to think I’d remember.) The default password of ‘admin’ could also be included with the install instructions…

Details: Plug it into my laptop, set the laptop’s address to a 192.168.1.* subnet address, point the browser at the bridge, and go through the steps. Pick a name for it (dora, since that’s who P was insisting he wanted to see on TV at the moment), first enable WEP, make it use a 128-bit key and hit Apply to have it actually accept a longer hex key, give it the key, and let the bridge restart. Then change its address and gateway, Apply, again it restarts. Change my laptop back to its correct subnet, again point the browser at the bridge using the new address. Meanwhile go onto our DHCP server, make the bridge get assigned its own specific address, and also add the name and address to our local nameserver. Now tell the bridge to use DHCP to get its address, and again restart. Yeesh. Unplug everything, put it down next to the tv-box, plug the Ethernet cable into the tv-box, and let everything start again. Laptop can ping both Dora The Bridge and the tv-box. Whew.

Next time I can work on this, I should be able to configure channels without worrying about plugging the tv-box into the network. That’s really the big task coming up: selecting “Watch TV” from the MythTV interface and making it actually show a channel. Don’t care what. 🙂

We decided to build our own PVR (personal video recorder) to make it easier to enjoy TV when we want to. With a son nearly 3, we’ve long known that our ability to watch random television programs is controlled by how tired we are. Since TiVo doesn’t have any service in Ireland, and we don’t want to buy the alternative service that is around Ireland and the UK, we’re rolling our own. (The privacy addict that I am hesitated mentioning Ireland here, but there’s already enough evidence on public record about our existence in Ireland, so why not.)

The goal is to make a device that’ll save TV shows for whenever we choose to watch them, but with more convenience than usually comes from a VCR. In particular, we don’t want to be restrained to the length of the tape that happens to be in the VCR at the time. But we would like to be able to save the programs we enjoy watching so we can take advantage of recreational time when it presents itself. (Our current favorites: The West Wing, CSI, Law and Order, and Gilmore Girls.)

Right now in the livingroom is a Shuttle SN45GV2, which is a tiny (SFF — Small Form Factor) PC. It’s got a 250Gb disk (from the states for $139, tho E just found one for $80 that’s even bigger), 512Mb of memory, a Radeon 9200 video card that I got near home with my friend Declan, and a Hauppauge PVR-350 tuner card to actually get at the TV signal. The PC has a long Ethernet cable at the moment, but it’ll soon be using the Linksys 54Gbit wireless bridge that I got today to let it be on our network without a wireless card in the computer, and without stringing a cable along the floor in front of our fireplace.

The tuner card is interesting because there’s nothing on its packaging to suggest that it matters where you buy it, Europe or the US. (TVs in one area use different signals than another, making them not work from one place to the other.) A friend was over in the US and brought one back for me; everything looked great. In fact, if you visit the link for the card you’ll see the page that says, ”Note: The WinTV-PVR-350’s TV tuner and S-Video/composite video inputs are for either PAL or NTSC.”. That’s actually wrong; the tuner, when you take it out of the box, has a big sticker on it that says “NTSC / NTSC-J”. Gah. I verified that it will not work properly with PAL-I signals coming over the wire here in Ireland. So I had to go get another from someone here. Voila, no markers on the box, but on the card is a “PAL-I” sticker.

In goes the card, up comes the computer, and after booting and some bit-tweaking (to be detailed later) I saw a successful test pattern on the TV screen. Yay!

Now that it’s working, and I’ve gone through the steps with mythtv-setup to make it understand the basic parts of how I’ve got everything set up (also to be detailed later), I have to make it grok the frequencies of the NTL basic cable. Haven’t had a chance to do that yet, and I start some work tomorrow (11 days of fun C++ stuff), so I suppose I’ll be working on it in the evenings somehow. Or maybe the weekend, though typing in the livingroom around our son is an exercise in futility. What time I may have had today was eaten up by making this blog exist, getting a toner cartridge, and the wireless bridge.

Tsk, tsk, it’s all about time management.