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| March 2007 |
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| Thursday, 1 March 2007 | Echunga | Images for 1 March 2007 |
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Autumn is finally here! It's been a long, dry summer, and the change of calendar doesn't seem to have made much difference. Hopefully we'll get more rain soon.
Woke up just before to discover that during the night we had had not one, but two power failures. The second one had already been going on long enough for my main machines to have gone down, and it continued for another 2 hours. Now the longest uptime I have is 48 days, with my brewing fridge machine, which apparently has the best relationship of UPS backup to power consumption. These continual power failures are really getting on my nerves. One good reason to have wind or solar power is that the whole house is effectively continually on UPS, and that it's the mains power supply that is the “backup”.
More work on MythTV today. This is really like pulling teeth. In the course of the day, discovered that there's something I still don't understand about attaching “inputs”. It could be my imperfect understanding of how things fit together, but at the moment it looks more like a bug to me. I had already mentioned that mythtv-setup produces a warning about incorrect channels when exiting. I was unable to get rid of it, and ended up looking at the underlying MySQL database, which showed that yes, indeed, the information in the database was incorrect. Either mythtv-setup is setting up the channels incorrectly, or the documentation is so bad that I still can't work out what's going on.
Things were not all plain sailing after that; mythfrontend still claimed that no channels were defined. In the end, did a complete scan, which added all channels in addition to those derived from the guide data. After that, I was finally able to schedule a recording, only to discover after the event:
Clearly there's something seriously wrong somewhere. Time to revisit the database.
In the process, ran into more trouble with the new cxm driver: it failed to tune to the channels. After some experimentation, including rebooting to change to the old driver (which worked perfectly), discovered that tuning would succeed if the old driver had been run previously. Further investigation shows that the old driver, but not the new, automatically selects the tuner when you try to tune to a channel. The new driver (currently) requires the -t option to select the tuner.
| Friday, 2 March 2007 | Echunga | Images for 2 March 2007 |
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The work on MythTV continues. Came in this morning to investigate why the recording I had set up for last night had failed. Presumably the important message was:
That looks very much like a problem with the channel number. Further investigation in the database revealed that the programme guide had not set any channel numbers. Here a couple of channels:
The first two were set up by the programme guide data; the second two, the same channels, were found by the “channel scan”, which doesn't seem to have done anything beyond including all possible channels in the table. Ended up having to use SQL to set the channel numbers and frequencies.
Things still didn't work too well, and I discovered that I had programme data only for SBS. Followed up on a message from Alex Wilkinson and installed a new guide data grabber, tv_grab_au_reg, which confuses the Ports Collection by being a single, uncompressed shell script. Spent a lot of time trying to work out how to explain that to the Ports Collection before giving up and just installing it. MythTV didn't like the change in grabber, and in the end decided it would be easier to remove (well, move aside) the database and start again. That wasn't that simple either: MythTV doesn't create the database if it doesn't exist, it just goes crazy. Finally got the thing installed, writing instructions in the process. tv_grab_au_reg can handle all the data it receives, or filter only those channels you specify. MythTV is not so clever: if you don't specify any channels, it doesn't recognize any of the data it gets.
Finally pulled in the data and discovered the times were off by 10½ hours; unlike the older tv_grab_au, you have to set Auto in the TimeOffset field.
Finally all was in place, and I really had guide data for all 7 channels—but I had lost my channel frequencies again. Put them back in and I was finally, for the first time, able to record a programme from TV using only MythTV. After only 2½ years!
| Saturday, 3 March 2007 | Echunga | Images for 3 March 2007 |
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Building on yesterday's success, spent a lot of time today documenting what I had done. There's still a lot of stuff to remove from the documents, but hopefully they'll fill the gaps where so much documentation falls down: document not just what to do, but what to look out for. So far I haven't been able to get the channel data included automatically, for example, so my tv_grab_au_reg document explains the problem and how to solve it.
Then spent some time installing MythWeb, a web-based interface to MythTV, requiring of course all the myriad bits and pieces of Apache, MySQL and PHP. After installation, nothing much displayed, except for the entries in the Apache error log:
Nothing indicated what the child was, but a tail -f showed that it happened when I tried to load the home page. Tried it on echunga, where it worked (modulo not being able to access the database), so compared the httpd.conf files and discovered:
The first entry is what I put in there. The second, with the strange spacing, was added by the port, which didn't first check that the entry was there. For some reason, this double entry was causing the SIGSEGVs: after removing it, things worked well, and displayed reasonably useful information:
There are still a number of things to fix, of course. Firstly, the colour scheme is emetic, the rendering incorrect, and there's a PHP error message at the bottom that I need to attend to. Still, a good basis for building something useful.
In view of the impending multimedia boom, decided to upgrade Yvonne's machine, battunga, which is still running FreeBSD 4.9. Things didn't work well: the first disk I found was from one of the machines that was killed in the December 2005 power surge. It became very clear that the disk had also been affected: the clunking noise on spinup was accompanied by a burning smell. I wonder how high that voltage spike was.
The next disk installed fine, but when I tried to reboot a new kernel, it hung with uncorrectable I/O errors. Looks like time to buy a job lot of, say, 20 GB drives.
| Sunday, 4 March 2007 | Echunga | Images for 4 March 2007 |
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Out riding in Kuitpo forest again today, but the horses were anything but active, and we packed it in after only 45 minutes. We really need to keep them better in form.
Continued work on MythWeb, and found the cause of yesterday's error message (easily enough, given that it was accurate and said what the problem was): it seems that MythWeb tries to save state after every display, but for some reason it opens the database at the beginning, then closes it (where? I can't find that), and then tries to write to it. Kludged around that by reopening in the function itself, but it brings home to me how little I understand about debugging PHP.
Also spent some time playing around with the CSS style sheets, something else I don't really understand, to try to fix the horrible colours. Ended up with a black on white rendition which is probably too much oversimplification. I wonder what it would be like to simply invert all colours, and how best to write a script to “fix” the style sheet.
| Monday, 5 March 2007 | Echunga | |
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Spent a lot of the day refining my new system installation techniques, something that I've been dabbling with for years. It's still not perfect, but I'm close to the situation where I can write a description file with port “nicknames”, short names that are not necessarily unambiguous, but which are defined in more detail in a separate file, and then say make ports to have them all installed.
The problems I have are:
Also some work on MythTV, and committed a number of related ports.
At the request of many, also committed updates to the sleep(9) man page. People still aren't happy. What a mountain out of a molehill.
| Tuesday, 6 March 2007 | Echunga | |
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Last October I went to the dentist with some gum problems, and as I noted at the time, I was less than happy with the treatment. The problems haven't gone away, and the dentist's advice (“All you can do is brush your teeth”) seemed implausible, so today into town to a new dentist, who promptly sent me off to a periodontist. Both were much more on the ball than the bloke in Mount Barker, but it looks as if I'm going to be in for some fairly rigorous treatment.
Somehow that took up all the day. By the time I had got home and had lunch, it was 15:10, and didn't get much work done.
| Wednesday, 7 March 2007 | Echunga | |
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More work bringing up a new version of battunga today using my new system installation methods. On the whole it works well. The biggest issues are:
Ensuring that the port installation rules are correct. They work by looking for specific files; if this file is not installed by the port, the installation will be repeated every time you run make ports. If it's installed by something else (as well, maybe), the port won't get installed at all.
It relies, of course, on ensuring that all configuration information from the old machine has been saved. Otherwise you can end up with regressions.
It also relies on a deterministic relationship between the files and their RCS symlink. For example, I found the following in battunga's /etc/namedb:
$ ls -l /var/tmp/battunga/etc/namedb/
total 1
-rw-r--r-- 1 root wheel 427 Mar 23 2004 PROTO.localhost-v6.rev
-rw-r--r-- 1 root wheel 423 Mar 23 2004 PROTO.localhost.rev
lrwxr-xr-x 1 ftp nogroup 48 Mar 20 2005 RCS -> /echunga/home/Sysconfig/MasterRCS/etc/namedb/RCS
drwx------ 2 root wheel 512 Mar 7 14:45 RCS.local
Clearly that won't get reinstated in the new installation.
Also spent more time looking at MythTV. There are so many things I need to do next that I don't know which should be done first.
| Thursday, 8 March 2007 | Echunga | |
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10 years ago today I returned to Australia after spending most of my life in Europe and Asia. How time flies!
Resolved my question about what to do next by deciding that it would make most sense to get my current recording setup converted to MythTV. That involved mainly setting it up on ceeveear, which was based on KnoppMyth. Spent some time reading the documentation, but there's very little there about multiple back ends, so just tried setting it up. The configuration seemed to work well enough, but for some reason it wanted a duplicate set of guide data; it seems that MythTV defines a master backend, but it doesn't do the logical thing and keep all the data in a single database.
Rather than setting up the guide data from scratch, copied the configuration from tv2 and renamed it to match the input. That still didn't work too well; after realizing that ceeveear didn't have a default route to the outside world, managed to do an update. But what did it really do? It's difficult to say from this output:
The 39 generic episodes suggest that it loaded something, but the numbers didn't inspire confidence. Carrying on, though, it was clear that there was something wrong:
The backend server is tv2 (why does all this stuff use IP addresses instead of DNS?), and it's running MythTV version 0.20a. ceeveear was a long way behind that, but since it's a Debian box, it's easy to update to the latest version, right? Well, yes, but since it's Debian, the version installed was the latest version. Instead went off looking for the sources for MythTV, which proved more difficult than I thought, considering I've done a port for FreeBSD. In the end decided to check out from the Subversion repo.
In the meantime, took another shot at getting Ubuntu up and running on my new prototype box (the “black box” I was using for other purposes for so long). Again it couldn't get X to run, so ran an xterm on wantadilla and tried to start Emacs. No Emacs installed—indeed, I had not been given any choice of what to install. It was on the DVD, of course, but it looks once again as if I'm going to have to install every little piece manually. This is really a pain.
That was nothing, however, compared to what happened when I ran Emacs: it crashed the X server on wantadilla with a SIGSEGV. That's the first time I've ever seen that, in 17 years of running X on my desktop. Somehow every time I try to use Ubuntu, I find it more annoying than before. Decided to download a Fedora Core 6 DVD ISO image instead, but that takes hours, so I didn't get anything finished.
| Friday, 9 March 2007 | Echunga | Images for 9 March 2007 |
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Graham from Echunga Sales and Service (the local car repair shop) along today to pick up our old Citroën CX:
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Somehow that's another “end of era” situation. I don't think I'll ever buy another Citroën, not because I don't like them, but because my life has changed.
More work on getting Linux to work on my CVR boxes today, and somehow seemed to spend all day without achieving very much. I probably owe Ubuntu an apology: KnoppMyth R5E50 (where does he get these revision numbers from?) also did so. Couldn't install Fedora Core 6: after burning the DVD, discovered that firefox (my favourite program) had stopped downloading in the middle and hadn't reported the error anywhere where I could see it, so used ftp to download the rest. For some reason that came up with an invalid checksum, so I repeated the entire download with ftp. It proved to be that I had used sha256 instead of sha1, but I didn't find that out until after downloading and confirming that both images had the same checksum.
| Saturday, 10 March 2007 | Echunga | |
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Decided to give up on installing Linux on the Via motherboard (“black box”) and do some reshuffling. My main concern is to not be in a position where I can't record TV, so decided to put the disk for the tv2 FreeBSD box in the black box and use the other system for Linux.
That brought another problem with itself: I also needed the Linux box (which I called cvr2) in the Hi-Fi cupboard, because that's where the antenna connections are. But the switch there (also wireless access point) only had five connections, and with tv2 they were all in use (uplink, downlink to the VoIP ATAs in the old office, ceeveear, teevee and tv2). Ended up switching the switch in my old office (8 ports, only 3 in use) with the access point. And that again was complicated by the fact that the access point had a 115V power supply, so I had to move the transformer, disconnecting the other power cord, which I had thought was the old TiVo that I no longer use. It wasn't until later that I discovered that it was for the amplifiers in the old analogue video switch, meaning that the TV no longer had an input. What a pain!
In the end gave up with the display on cvr2 and left it in the black box; I only really need this as a test box for the MythTV backend. The good news is that the DVICO tuner card that had given me problems earlier now worked fine; I had suspected that this might be a driver issue, and the new version of KnoppMyth has a relatively new kernel (but very old versions of dvbscan and tzap). Spent still more time trying to set up MythTV like that, but it seems that the channel setup is still a serious issue. It seems that both Australian TV guide grabbers provide some information, but not enough, and none of the instructions I found (specifying unknown grabbers) worked for me. It should be possible to create this information from the output from dvbscan, and maybe I'll do that.
| Sunday, 11 March 2007 | Echunga | Images for 11 March 2007 |
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Continued with channel setup for DVB today, and got some useful help on the #mythtv-users IRC channel. As I suspected, it's all a question of documentation. All along I had expected that tv_grab_au_reg or similar should miraculously produce the tuning information, but despite the documentation this isn't the case: it just provides the channel IDs. For DVB-T, the tuning information can come from one of two places: from the internal scan or from the output of dvbscan, exactly what I hand been planning to do. The tuning information for DVB is currently (MythTV version 0.20a) shared across two tables. The channels table contains information for both digital and analogue channels, but for digital channels the freqid attribute is ignored. Instead, it is linked to the dtv_multiplex table via the attribute mplexid. dtv_multiplex contains transponder information, notably the frequency, bandwidth and modulation stuff—much the same as what dvbscan outputs. There must be other stuff as well, but so far I haven't found it.
Tried both methods and decided that I'm more comfortable with the channels.conf file method. Here's how to do each:
To scan with mythtv-setup, you first need the guide data properly installed. With tv_grab_au_reg this means that you need to exit mythtv-setup and follow the instructions to get the guide data (I think). Restart mythtv-setup if necessary, go to Input connections and select the tuner input. Select Scan for channels, then select Full Scan for Scan Type. This works, but the output worries me, since all I see are failures.
Run dvbscan to get the channel information.
Start mythtv-setup, go to Input connections and select the tuner input. Select Scan for channels, then go to Scan Type and press the left or right arrow key until Import channels.conf appears. Enter the name of the file in the File Location field.
In either case, you may want to tidy up the channel information. In my case I ended up with 32 channels (6 analogue, 26 digital, including programme guides, duplicates and radio). If you're using both analogue and digital tuners, you'll need to ensure that the channel information is linked to the same programme guide data. This is done via the xmltvid column.
In addition, 32 programmes are a real pain to view on screen. MythTV only displays those channels who have the value 1 (and not, for example, 2) in the column visible. You can always update this using mysql with commands like:
It's a lot easier with MythWeb, though. One of the selections in the Settings menu is channel info, and there you can select the visible attribute and set the xmltvid directly.
In the end, you should be able to see something like this:
Here the chanids in the range 15xx are digital, and the chanids in the range above 3000 are analogue.
After doing that, it's definitely a good idea to save the channel information. I've saved the information for Adelaide here. This is mysqldump output, so it can be installed (overwriting previous tables!) with:
After all that, finally had a properly running backend with digital input. Things are looking up.
| Monday, 12 March 2007 | Echunga | |
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Today spent some time—far too much time—looking at how to get multiple tuners working in one machine. It's not easy, and I didn't manage completely.
I ended up adding two other tuners: the second (really the older) DVICO tuner and the MSI TV@nywhere analogue tuner. The first problem was just entering the device name. The first DVB-T tuner had the device name /dev/video0 in capturecard.videodevice, and (not surprisingly) the system came up with the devices /dev/video1 and /dev/video2 as well. But I couldn't find a way to enter /dev/video1 with mythtv-setup. Tried it with mysql, which worked, but then I ended up a non-functional mythbackend which ignored the device name and tried to open adapter 0 twice. After a lot of trial and error, two things became apparent:
My best guess is that the code is using atoi or a similar function to convert the field into binary, and not checking whether it's valid. atoi always returns 0 if pointed at a non-numeric string.
So, finally I can record two things at once. As MythWeb reports:
The adapter numbers are the result of MySQL's autoincrement feature. At some time I'll fix them. First, though, I need to get the analogue tuner working too.
| Tuesday, 13 March 2007 | Echunga | |
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Into Mount Barker today for an X-ray, which took all of 10 minutes. Nevertheless it seems to have completely broken up the day. While there, met up with Yvonne, who was shopping, and rented far too many DVDs.
Ans Papini along in the evening with some people interested in the house. Who knows, we might sell it yet.
| Wednesday, 14 March 2007 | Echunga | |
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Somehow didn't get anything done today. Spent all the day playing around with hardware, but at the end of the day didn't have any more to show than having added a 250 GB drive to teevee. Started by putting it on wantadilla as a USB-attached disk, but for some reason it did a spontaneous reset when I tried to newfs it. it. Finally managed to shoot down teevee as well, so put the disk in on an ATA connection.
More problems recording programmes in the evening: one of the recordings didn't work correctly. Do I still have a problem with one of those DVICO cards after all?
| Thursday, 15 March 2007 | Echunga | Images for 15 March 2007 |
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Another power failure in the middle of the night! This is really getting on my nerves, especially since it's currently so difficult to get tv2 up after a reboot. Got up in the morning and discovered that I had also lost the ADSL line from 23:00 to 01:00, and that the routing for my main address was still flaky. Called Internode, which took a surprising amount of effort, and of course they had to hand it to second-level support. At least the class C network is working, but it meant moving a few things around.
Looking at yesterday's DVICO recording problems revealed that they only worked incorrectly on a single channel, my favourite Nine MSN. Also discovered that the two cards aren't identical after all: they have a different demodulator chip, the Zarlink ZL10353, about which I have heard of other problems. Looks like I'll have to upgrade the drivers, or, better, write a driver for FreeBSD.
Another bloke along in the afternoon to look at the house. He's looking for somewhere he can build a 700 metre air strip on. That would just about fit here. He came flying by a little later to take a look, but to judge by the single pass, he must have found something he didn't like.
In the evening another power failure. This is driving me mad, and caused me to spend some time rearranging UPSs so that all the machines in the HiFi cupboard are on one big UPS.
That didn't help with my recording, unfortunately. In the middle of a recording in the evening, the recording just stopped. If there was an error message, it's not clear where. Spent over an hour messing around trying to find what was going on, during which the “good” DVICO card stopped producing any output, despite good signal, and mythbackend refused to start. Finally gave up in disgust. What a day!
| Friday, 16 March 2007 | Echunga | |
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The cause of yesterday's problems could have been in part due to the way I set up the channel table, so decided to start again from scratch today. That worked better than I had expected:
This left me with a whole lot of channels with no guide data, and a whole lot of guide data with no channels. This time I used the MythWeb channel editor to set the xmltv id for the channels in question. I wonder how it's meant to be done.
In the process, discovered that the attribute sourceid relates to the tuner number, so it is possible to restrict certain channels to certain tuners. That'll be handy with the current Nine MSN problems. It's also interesting to note that you can run mythfilldatabase several times before it finds nothing more to update, though typically the changes are things like:
After all that, ended up with multiple displays for each program, one per tuner card. I don't have a good idea of how to fix it; probably I'll have to hack MythWeb.
Also a call from Richard Panic, an aptly-named insurance assessor for ETSA. He'll come along on Wednesday to look at the damage caused by the power spikes on 6 December 2005 and 10 January 2007. Not too early.
I later discovered that it's Richard Penneck, not Richard Panic. I still prefer the latter.
As of midday, my IP routing was still messed up. Called the Internode support line again, and this time waited until I was answered, by far the longest wait I've ever had to reach a telephone support line: 84 minutes. When I finally reached somebody, I was told that I should have chosen the “business” option from the telephone menu, and I would have been attended to right away. There are two problems with this: it doesn't help non-business customers, and there was no menu. I was told I should have called 8228 2999, not the 8228 2911 that I called on the instructions at support contacts page, which incidentally took me nearly 2 minutes to reach via three incredibly slowly loading pages.
I suggested that the information should be updated, but the support person didn't see any reason to do so, since the information was “correct”. What's he thinking?
The lack of action about my routing issue was due in part to the fact that my mail server was on the machine with the routing issues, and though I had thought that the problem would only affect other ISPs, it proved impossible to reach the Internode mail server, ipmailmx.internode.on.net, so my message was still hanging in the queue. It included traceroute output which would clearly help things; but is that a reason not to do anything? Most customers wouldn't know how to run traceroute. That's not a reason to leave a serious routing issue open for over 24 hours.
Finally got the message through to him by copying it to freefall.FreeBSD.org and mailing from there, and finished the phone call after 129 minutes, not very satisfied. I've always been supportive of Internode, but the service I've had lately has been unacceptable. By the evening the problem was still not resolved. If I hadn't had the class C network, something that almost nobody has, I would have been off the Internet for two days. Hopefully Internode will improve. At the moment I don't see any reason to change to another supplier: I fear that this is a sign of the times. Recently c't magazine did an article about the terrible network support currently being offered in Germany. I could well imagine that the same would apply here.
Decades ago I claimed that it was impossible to make a good pizza at home. At the time it was the general lack of understanding about how to make a salsa pizzaiola, but since then I've had difficulties getting the base cooked properly. The obvious problem, of course, is that most people don't have a real pizza oven, which heats the base from below (look at the underside of a good pizza; it's quite browned). Today finally did the obvious and set the oven to heat from below and then put the pizza in a tray on the oven floor. It was so much better that it was almost overdone. Next experiment is to do that for 5 minutes, then grill, with a thicker base.
| Saturday, 17 March 2007 | Echunga | |
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Up early today with the intention to address the issues I have with MythWeb, and discovered that it's more difficult than it seems to change. Made a horrible kludge to select only one instance of each channel, but it's specific to my current database setup, and it desperately needs improvement.
Then out riding with Yvonne and Diane Saunders, spending more time preparing than the 45 minutes we actually rode. It's been some time since we have gone out for any long ride.
Back home and discovered that MythTV had decided to record everything from the analogue tuner, and I couldn't find a way to make it change its mind. Reading the documentation, I found:
The Master backend will always choose the first available tuner in the same order as you add cards through "mythtv-setup". In other words, the second card you add will only be used when there are two overlapping recordings, the third when there are three, and so on.
In fact, it was using tuner 8, the last of the three: the tuner number is in capturecard.cardid, an autoincrement field that leaves you with numbers reflecting the number of attempts you have made to install tuners. In my case, the numbers were 6, 7 and 8, so the master backend should have been using tuner 6, then tuner 7, but it seems that they didn't get stored physically in that order:
So it seems that the order is the order in which they're stored in the MySQL table, not the order in which you add them. But the sequence in a MySQL (MyISAM) table is indeterminate, even for primary keys (in this case cardid). Rebuilt the table so that the physical sequence matched the numerical sequence, but still couldn't get it to stop. In the end removed most channel entries for the analogue tuner card, leaving only channel 31, which doesn't have digital broadcasts. Clearly that's unsatisfactory: it should be possible to specify preferences.
Even that didn't work: recording an old Bonanza sequence gave me 32 GB of junk. Maybe it's related to the problems that KnoppMyth has with the sound chip on this particular motherboard, or maybe it's the driver for this particular card, which I've never had working. Maybe I can try it with the PVR 250 next week.
Another power failure this evening. This is getting to be too much. I've started an overview page showing how often we have these failures.
| Sunday, 18 March 2007 | Echunga | |
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Slow day. Spent some time writing up what has been happening lately, then watched TV a bit. All this work on computer video recorders has left me little time for that kind of activity.
Brian Aker, Director of Architecture at MySQL commented on my entry on MyISAM yesterday, saying that the values returned are based on the order of the INSERT. That's correct, of course, until you start deleting rows and then inserting new rows. Where they end up depends on a lot of things, but it's clear that MyISAM reuses the storage space. Under the circumstances I'm talking about, it returns the data in the sequence it's found in the table, which is dependent on too many things to be relied on.
My comments on pizza last Friday drew a couple of responses: Tom Maynard pointed me at a method involving the use of a cast-iron skillet, a kind of frying pan. Some of the details look a little dubious, including the mention of a temperature of “800 degrees” (about 430°), which seems far too hot to me. He also talks about cooking for only 1 minute 35 seconds, which confirms my suspicions. But the method is similar to another one I was thinking of, though: at least in Australia, a gas barbecue has a large cast-iron plate for frying on. Until my recent experiments, I had been meaning to play around with that for doing a pizza: almost close the lid, blow air across the top, and you have a good approximation to the environment in a pizza oven. The main reason I haven't done so is because it's so difficult to control the temperature, especially if there's any wind at all.
Also, Michael Hughes pointed me to a pizza stone, which works by storing heat and then applying it more evenly to the pizza. This is quite a good idea, though the one he shows looks a little small (which means that it will cool down more quickly). In all probability this is a better solution than the one I use, though that remains to be seen. In any case, mine is cheaper.
Tried another pizza tonight. Since the last one had a tendency to be overdone, I cooked this one less on the bottom, then grilled for the remaining time. I also made the base thicker. The combination was not optimal; the base wasn't completely done through. Clearly there's some more experimentation to do here.
While watching TV this evening, had another power failure. Again, only a couple of seconds, but it set the UPS on echunga into an alarm condition, rebooting the machine in the process, and it damaged the projector bulb—which costs over $500 to replace. I wish I understand what's going on here, but it looks like these outages are often accompanied by significant power surges.
| Monday, 19 March 2007 | Echunga | Images for 19 March 2007 |
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Spent an inordinate amount of time looking for a new projector bulb today. The prices are high, and they also vary a lot. It seems that the best prices are in the order of $330, from sources in Japan such as PriceJapan, and they could take up to 3 weeks to deliver. In Australia, finally found a bulb from Discount Projectors in Richmond, who went to a lot of trouble to ensure that the globe (at $545!) would be in Adelaide tomorrow. That's a lot of money for 3 weeks TV watching, but not for peace of mind.
Also called up ETSA to ask about the causes of the problems and how to solve them. Got a promise of a call back within 48 hours for the explanation of all the power failures, and a “voltage investigation” within 20 days. Hopefully they'll find something there.
Tony Arthur along in the afternoon with another machine to install FreeBSD on. I had all this prepared, but of course lots of surprises occur when you actually try to do something, and spent most of the afternoon refining my build processes.
My ADSL line is still off the net. Some time in the afternoon I got a message from Internode support asking for the traceroutes I had prepared on Friday—their reporting system had assigned them another ticket number, though I had included the first in the message, and this seems to have been enough for it not only not to be connected, but also to be lost for a day. I'm still not at all happy with the progress, and by the evening, beyond the report that they suspect an “odd-even” problem with Telstra, nothing had happened.
| Tuesday, 20 March 2007 | Echunga | |
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Phone call this morning from Shaun, a Customer Care person from ETSA this morning. He didn't do his job well. At the end of the 35 minute discussion, I was far more annoyed than before. It seems that the main point of his uninformed and partially completely wrong statements was to absolve ETSA of any blame for what has happened. Here are the full details.
Call from Internode with the news that the network problem had been resolved—sort of. I'm still getting 5% packet loss to some places, but it's a lot better, as the statistics show:
The brown line shows the number of systems reachable, out of the 5 that I have chosen.
Daniel O'Connor called before 10 am to tell me that the projector lamp really had arrived. Clearly there's a big difference between deliveries in town and in Echunga. Into town in the afternoon, picked that up, and then to Leader to get some more multimedia hardware, in the process bumping into Phil Tann, who is currently trying to migrate to FreeBSD. Then to a special general meeting of the ICT council. Looks like we're setting up to change direction again.
| Wednesday, 21 March 2007 | Echunga | Images for 21 March 2007 |
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Richard Penneck, the insurance assessor, came in today to inspect only the damage done by the December 2005 power surge. The letter to ETSA clearly stated that most of the damage was done on 10 January 2007, but he was not asked to assess it; I suspect that ETSA hadn't read the letter carefully.
Started putting together the next generation CVR, with a rather nice motherboard including firewire, gigabit Ethernet and an nVidia graphics chip, along with the AVerTV Hybrid+FM PCI card. Installation with KnoppMyth was not encouraging: it didn't recognize the graphics chip, and it didn't recognize the tuner card. Maybe they're both too new; hopefully I'll be able to sort it out, but it's still not plain sailing. Brought up FreeBSD on the machine and confirmed that it didn't recognize the graphics chip either, though at least it was able to install a VESA driver and display something.
Also changed the bulb in the projector. Looking at the bulbs, it's hard to see why the output should have diminished. You can barely tell them apart:
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The one on the left is the old one. It's also difficult to see why they should be so expensive.
| Thursday, 22 March 2007 | Echunga | |
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Work on two fronts today: continued installing the “black box”, and ran into significant trouble with the Hauppauge PVR-250 card, which failed to probe. When loading the kld I got:
After much head-scratching noticed that this message was followed by:
That shouldn't have happened. Since I didn't need the card, decided to remove it, and contrary to my expectations it fixed the problem, which doesn't seem to have anything to do with interrupt sharing.
With the other machine, installed the nVidia driver, which contrary to my fears did recognize the graphics chip:
Created an X configuration file, started X and—it spontaneously rebooted, repeatably.
Rather than follow that track, tried installing Ubuntu Edgy, which installed correctly, the first Linux installation that has been able to start X for some time. Then tried installing the nVidia driver. For FreeBSD it's simple:
It's not quite that easy with Linux. You need to:
After this, the driver ran fine. I suspect that the problem with FreeBSD was that I had set the DIAGNOSTIC option in the kernel, which catches program bugs that normally go undetected. But that's for another day.
The display card, the AVerTV Hybrid+FM PCI, is another matter. After reading the details more carefully, it seems that it's not supported properly after all. Leader doesn't want it back, so it looks as if I'll be in for a wait until somebody—maybe myself—adds support for it.
How much brighter is the new projector globe than the old one? It's a lot; I had expected that the old one had lost at least 90% of its output. But how do you measure it? Decades ago I did some photometry work with my camera, taking photos of grey scale to compare with the exposure meter of my camera. I've forgotten what conclusions I came to at the time, but this time I used the same camera to measure the light intensity looking directly into the projector while it displayed an xterm. The results: old globe, ½ second at f/5.6. New globe 1/250 s at f/5.6, or 125 times stronger. That's quite amazing.
| Friday, 23 March 2007 | Echunga | Images for 23 March 2007 |
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I was supposed to go into town today to the dentist, but the car thought otherwise: the ignition lock jammed up and couldn't be turned. Yvonne was in Mount Barker with the Magna and came back as soon as she could, but we had to postpone the appointment.
Back into Mount Barker with her, passing by the car workshop on the way. Graham now has the CX engine running, but it looks like he'll have to do some serious overhaul work on the gearbox. He also told us that there wasn't much we could do about the ignition lock except replace it. That'll be fun.
In Mount Barker, went shopping at Woolworths. They value their customers, and don't like people leaving:
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The door with the word “EXIT” above it is an emergency exit; the sign on the door itself states that an alarm will sound. Where's the real exit? Next to it on the right, without a sign.
In the afternoon, checking why I couldn't access MythTV database on ceeveear. The answer was simple: it was set up that way at install time, without any information. That's not the default, and the following change was all that was needed:
Why do people do these things?
That wasn't enough, unfortunately. For some reason there's a protocol difference between front and back end. They're both supposed to be the same version, so that puzzles me. Still more work needed.
| Saturday, 24 March 2007 | Echunga | Images for 24 March 2007 |
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Set to installing a compatible version of MythTV today; fortunately Geoff Buckingham had sent me a port of the “stable” version, which is only available from the subversion repository. I wonder how we should handle this; there are at least three versions out there, and they all seem to be incompatible with each other:
Built that, and was finally able to get mythfrontend on FreeBSD communicating with a mythbackend under Linux. Now to learn how to handle the remote control, and how to tell mythfrontend about XvMC.
In the evening to a party on the corner of Kondoparinga and Rodert roads. Alan Mutton was turning 50, and he had quite a big outdoor fancy dress party:
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Unfortunately, today was the day that winter decided to come, at least from a temperature point of view (round 10°), and all was rather cool.
| Sunday, 25 March 2007 | Echunga | |
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As planned, spent some time today trying to get MythTV working with XvMC and with LIRC support. The former was complicated by the fact that the display cards on wantadilla use nVidia GeForce MX 4000 chipsets, and they're not supported by the current drivers. Installed the “legacy” driver, which for some reason brought up wantadilla:0.0 with a maximum resolution of 1856x1392. In the log file it stated:
This appears to be the opinion of the monitor itself; but it's been running fine for years at 2048x1536, and ultimately it's the horizontal frequency that determines the maximum resolution. Put that monitor back onto the nv driver and continued only with the second card, but that didn't seem to want to run XvMC either. Quite possibly the card doesn't support it, so I'll have to try on teevee. Some other day.
| Monday, 26 March 2007 | Echunga | |
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Back to working on the Black Box today, which wasn't much work, but which somehow managed to last the whole day. Debugging remote ssh problems is a pain!
| Tuesday, 27 March 2007 | Echunga | Images for 27 March 2007 |
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Over to Hahndorf to look at our prototype today, and got things sorted out pretty quickly. The biggest problem was the combination of DHCP server and misconfigured DNS. Why is it that DNS is such a problem in the Microsoft space?
Back home and found some people from ETSA about to leave after having placed a power monitor on the transformer. It seems that they really only intend to monitor the power under normal conditions, and that for a week. I'm sure they won't find anything. I'm reminded of the joke attributed to Josef Weizenbaum:
A policeman saw a drunk searching for something under a lamppost. “What have you lost?” the policeman asked. “ My keys”, said the drunk. The policeman then helped the drunk look and finally asked him: “Where exactly did you drop them?” “Over there”, responded the drunk, pointing toward the dark street. The policeman then asked: “Why are you looking here?” The drunk replied: “Because the light is so much brighter here.”
Did get some information from them, though: there can be significant power fluctuations if heavy power usage starts or stops, and there are capacitors in the power substations which, if they fail, can also cause significant fluctuations. They say that users of electronic equipment are advised to install surge protection. I can't recall ever receiving such advice, certainly not from ETSA.
Back home still had a few issues with the black box to address, including hang-overs from versions of the software written before I got involved.
Mail from Patrick Hess about the issues with the nVidia driver and EDID; as I suspected, you can turn it off with the following line in the DEVICES section:
That doesn't help with the fact that the card doesn't seem to handle XvMC, of course.
Finally got round to trying out MythTV with XvMC and with LIRC support on teevee. That didn't work either; the remote control failed with “unable to open socket”, and the XvMC with a more obscure error message. First, here's what happened with the standard codec:
At this point I selected the XvMC codec with the mythfrontend setup menu. Then I got:
This must be a MythTV issue, since XvMC works fine with mplayer. More to investigate.
Our “new” microwave oven is nearly 10 years old now (the old one is 23 years old), and almost from the beginning, the display started to fail, segment for segment. In the past few days it had got to the point where it was barely legible, and I was convinced that it was due to a flaky connector that just needed to be cleaned and reconnected, so took the control part apart and took a look:
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Unfortunately, I was wrong. The connector to the display is the ribbon cable at the top of the photos, and it is soldered. Looks like it's really a failing display. I don't suppose it's worth replacing.
| Wednesday, 28 March 2007 | Echunga | |
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Into Adelaide today to get my teeth looked at, with the result that the morning was gone. Spent the afternoon following up the MythTV with XvMC problems, with no progress. The LIRC problem proved to be a naming issue: in Linux, it creates a socket /var/lirc/lircd, whereas the FreeBSD convention is to put it in /var/run/lirc/lircd. Ended up putting in a symlink; I fear there will be more such cases.
| Thursday, 29 March 2007 | Echunga | Images for 29 March 2007 |
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More work with MythTV and XvMC, still with no progress. Got a couple of replies to my question on the mailing list, but they were at the level of “reinstall your nVidia drivers”. Frustrating day. Made up for it by cooking another choucroute:
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Once again we decided to change the proportions.
| Friday, 30 March 2007 | Echunga | |
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Had intended to look further at the XvMC issue today, but the black box got in my way, reminding me that we had stopped work a couple of months ago without reaching any clear status. The current version no longer runs as root, so we had various permissions issues to work around. By far the strangest was the continual flood of messages:
Looking at the devices showed nothing unusual:
=== logger@blackbox (/dev/ttyp3) ~ color="blue">10 -> ls -l /dev/cd*
Only with ktrace did I find:
So the permission problem was with /dev/pass1, not /dev/cd1. More sloppy programming.
| Saturday, 31 March 2007 | Echunga | |
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Intended to take it quietly today, so didn't investigate the XvMC issues any further. Instead considered the problems I've been having with the TV guide from tvguide.org.au and considered the alternatives. One is Shepherd, which culls information from a number of places. Installation—on Linux—was not as simple as it looked. It needs a whole lot of Perl modules, and in the process of installation I discovered cpan, which sort of makes things easier. But some of them required compilation, and that failed. In the course of fixing that, I discovered:
Of course, all this probably wouldn't have been correct if the instructions had been structured correctly: after working my way through them, I found instructions on how to do it with Debian. Presumably they would have been easier.
Setting up shepherd was strange. It ran for ever, and at the end it didn't produce any output. The instructions are rather vague about what it's supposed to do, but I'm pretty sure it should populate the mythconverg.program table. But it didn't.
Another issue with shepherd is that it doesn't seem to know about Adelaide channel 31. Decided to shelve that effort and try IceTV instead. That installed better, but still required running through mythtv-setup and clobbering the channel table. Ended up writing MySQL queries to fix it again. It seems that this is a common problem. The instructions specified that you should edit the channel table in mythtv-setup, but there's no documentation on how to do that, and the screen itself is unclear. With MySQL it's clear what needs to be done.
Unfortunately, that only gave me data for two channels, probably (as occurred to me later) because of the hacks I had put in my MythWeb source to only select certain copies of the guide data. Also, channel 31 still wasn't there.
Time was coming up for new recordings, so reverted to the old configuration (aren't database backups a good idea?) and looked at the next item, remote controls.
The wiki user manual describes the default remote control key bindings, but there seems to be no configuration file to match them. There are five sample lircrc files in the source tree, but three of them don't even relate to MythTV, and of the other two, one is be for the Microsoft Media Center Edition Remote, model 1039, not exactly a typical remote control. Started writing my own, but then wondered if I had missed something. Asked on the #mythtv-users channel on Freenode and had a surprising reaction:
IRC seems to bring out the worst in people such as Dagmar, but this fruitless dialogue shows a number of other issues with projects like MythTV:
| Button | Function |
| RecTV | Alt+R |
| Guide | Alt+G |
The syntax requires that this be changed into the following entries:
And as juski says, the names for the buttons vary from one remote control definition to the other. The names of the functions (“config”) also vary from program to program, which makes it particularly unhelpful to put in configurations for irxevent (which proves to be quite a useful program, one that I've been looking for). And so far I haven't found a definitive list of the names that mythfrontend is looking for.
Finally found a configuration file for a DVICO remote control by Chris Pascoe on Google, but it wasn't the same as the one I used. Set it up roughly, and it worked, but there's still plenty to be done.
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