This is just a quick post for reference. To tune MythTV for Ziggo Digital TV here in the province of Zuid Holland the following settings can be used:

Frequency:         372000000
Symbol rate:      6875000
Modulation:        QAM-64
The other settings can be left as ‘auto’

Make sure the decrypt card is in the slot. When I did it I got all the possible channels appear in the list so I had to go through the channel setup and delete all the channels that I don’t subscribe to.

For now I also decided to pull the Electronic Program Guide (EPG) information from the EIT data sent with the digital TV signal. It means I only get a few days of TV schedules (about 4 days) but it meant just ticking an option in the channels setup. Before I used to use the XML TV grabber scripts but the website it was pulled from changed frequently and broke the script, at least with the EIT data it should be a bit more reliable.

Apart from recording and watching TV the other thing we use the MythTV box for is the MythVideo plugin to watch all the Divx movies and other movie formats. Most of the Divx films are stored on a debian server and are NFS mounted to the MythTV server.

By default MythVideo will use the internal player for playback of all film types. This turned out to be a problem, I had collected a large selection of different films in various codecs and some of them would not play at all and some played with no sound.  I knew these files played ok because they had been on my old Myth box but there I had used mplayer as the default player so under Utilities/Setup->Setup->Media Settings->Video Settings->Player Settings I changed the default video player to be  mplayer -profile vdpau.

To make sure that mplayer used the nvidia ION chipset and VDPAU for playback I created a mplayer config file in the ~/.mplayer directory of the user that the MythTV fronted runs under and created the vdpau profile.

dougal:~/.mplayer$ cat config
[vdpau]
fs=1
tsprobe=8388608
quiet=1
vo=vdpau
ao=alsa
ao = alsa:device=hw=0.3
# Specify the mixer device.
mixer = default
mixer-channel = Master
ac=hwac3,hwdts,a52

The device number comes from the HDMI device in the aplay -l output :

dougal:~/.mplayer$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: NVidia [HDA NVidia], device 0: ALC662 rev1 Analog [ALC662 rev1 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: NVidia [HDA NVidia], device 1: ALC662 rev1 Digital [ALC662 rev1 Digital]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: NVidia [HDA NVidia], device 3: NVIDIA HDMI [NVIDIA HDMI]
Subdevices: 0/1
Subdevice #0: subdevice #0

mplayer seems to handle most codecs that you throw at it without any problems in playback and hardly use any CPU.

When I started thinking about audio I didn’t realise that Linux already had good support for audio with HDMI. I checked the playback options of my system with the command aplay -l .

$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: NVidia [HDA NVidia], device 0: ALC662 rev1 Analog [ALC662 rev1 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: NVidia [HDA NVidia], device 1: ALC662 rev1 Digital [ALC662 rev1 Digital]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: NVidia [HDA NVidia], device 3: NVIDIA HDMI [NVIDIA HDMI]
Subdevices: 1/1
Subdevice #0: subdevice #0

Looking at the options in the MythTV setup screens for audio playback one of the available options for device was ALSA:hdmi, choosing this just worked! Now playing back of recordings sends audio over the one HDMI cable to the TV which is perfect for me.

For some reason I couldn’t use the same for MythMusic so what I ended up doing was choosing /dev/dsp in the Music setup section for the audio device. This means I can use the normal audio output (the 3.5mm green audio jack) to connect to my Amplifier so music playback goes through my stereo speakers but TV audio goes through the TV speakers.

A thought occurred to me while I was thinking about the new MythTV setup which was that I hadn’t thought about how to control it from the sofa. The old setup I used had a Hauppauge PVR-350 tuner which came with an IR receiver to plug into the PCI card and a remote control. This was straight forward to configure under Linux and MythTV with LIRC.

For this new installation I didn’t have that luxury as the tuner card didn’t come with any IR attachments. I considered the possibilities, I could use a wireless keyboard (either bluetooth or usb attached) but that would require a keyboard on the coffee table all the time. Browsing the LIRC, there are a few descriptions to build your own USB IR receiver but I didn’t think my soldering skills were up to that. So I started googling around and ended up  finding a Creative RM-1500 remote control with USB IR receiver on ebay for under 10 quid. The guy selling it had several and confirmed on the auction page that someone else had bought one for use with Linux and MythTV and it worked fine. Done deal!

Since receiving it, I can now say it was incredibly straight forward to setup in Mythbuntu.  In the MythTV Control Centre just select enable IR receiver and choose Creative USB and then it works!

The other issue that I had not considered with the new setup was the audio. How would I get the sound into the TV?  The old motherboard used a S-Video cable for the video and an audio cable plugged into the standard ‘green’ audio out, all these cables then connected into the side of the old TV and it worked through the S-Video option on the TV. With the new motherboard and new TV I plan to use a HDMI cable from the PC to the TV and I am not sure what to do with audio ….

The assembly went ok so then I headed on to install Mythbuntu (which I had decided to try first) from an external USB DVD drive. Installation of Mythbuntu was incredibly straight forward and as I had decided this was to be a quick test install I just gave the whole 1TB drive over to it and it created one big root filesystem. My plan is to reinstall later and create at least two filesystems, one root and one for recording data.

When it came to setting up the tuner card I chose the DVB-C option but it didn’t give any feedback as to whether it had discovered it or not. After a little playing around with the DataSource and Input settings it became clear it wasn’t working quite right. I started looking at the dmesg output and found the following:

[    8.849587] Linux video capture interface: v2.00
[    8.940190] saa7146: register extension 'budget_av'.
[    8.940268] pci 0000:00:09.0: can't derive routing for PCI INT A
[    8.940274] budget_av 0000:01:0e.0: PCI INT A: no GSI
[    8.940320] IRQ 255/: IRQF_DISABLED is not guaranteed on shared IRQs
[    8.940326] saa7146: saa7146_init_one(): request_irq() failed.
[    8.940342] pci 0000:00:09.0: can't derive routing for PCI INT A
[    8.940358] budget_av: probe of 0000:01:0e.0 failed with error -22

This didn’t look good. After a little more delving I remembered seeing something on the mini-itx.com website about PCI risers:

Notes: Dual Risers only work with certain chipsets and motherboards. These Dual Risers are designed for boards with VIA C3 / C7 chipsets (i.e. most EPIA / Jetway boards), and with Intel Atom motherboards. To use with an Intel Atom board: put the IRQ jumper on the lower row, 3rd pair from the left. Untested / not compatible with other socket based Intel / AMD motherboards. We cannot guarantee compatibility with dual risers and all products.

Although it didn’t mention my motherboard or chipset I decided to take the motherboard out of the case and inserted the tuner PCI card directly into the motherboard PCI slot and this time the dmesg output looked much better:

[    9.813798] saa7146: register extension 'budget_av'.
[    9.814819] ACPI: PCI Interrupt Link [LNKA] enabled at IRQ 18
[    9.814831]   alloc irq_desc for 18 on node -1
[    9.814837]   alloc kstat_irqs on node -1
[    9.814855] budget_av 0000:01:05.0: PCI INT A -> Link[LNKA] -> GSI 18 (level, low) -> IRQ 18
[    9.814909] IRQ 18/: IRQF_DISABLED is not guaranteed on shared IRQs
[    9.814957] saa7146: found saa7146 @ mem f9b58c00 (revision 1, irq 18) (0x1894,0x0022).
[    9.814973] saa7146 (0): dma buffer size 192512
[    9.814980] DVB: registering new adapter (KNC1 DVB-C MK3)
[    9.853549] adapter failed MAC signature check
[    9.853558] encoded MAC from EEPROM was ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff
[   10.117418] KNC1-0: MAC addr = 00:09:d6:6d:91:0f
...
[   10.504977] DVB: registering adapter 0 frontend 0 (Philips TDA10023 DVB-C)...
[   10.505476] budget-av: ci interface initialised.

Mythbuntu then gave some feedback straight away when I choose the DVB-C tuner card and it would search for channels.

The PCI riser did have a very long jumper on it.

I tried all the different jumper settings, one of them gave a slightly different result in dmesg but there were a lot of timeout messages for the saa7146 device.

I gave up trying to get the two slot PCI riser to work as I don’t need the option of two slots and have ordered a PCI riser ribbon cable from ebay which I hope will solve my problems.

All of the parts arrived and I have assembled them. The first problem I encountered I was half expecting, although the case I ordered was a 2 slot PCI case the lower of the two slots could only take a half size card as the 3.5″ harddrive shared part of the space. Luckily this wasn’t too much of an issue as the case had space for a slimline optical drive and I was able to use this space for the CA/CI card module.

Fully assembled without top

The only issue is that there is a bit of a gap around the card module which sticks out the front of the case, this is fine as far as I can easily access the smart card but obviously is a bit ugly. There was a front plate that came with the CI card but it was for the space of a floppy drive, we’ll have to work something out to cover the gap.

Rear view showing PCI card and HDD conflict

Another pic below showing the PCI slot area with the HDD using up some of the space for the lower slot.

Want more pics? Let me know.

In my previous MythTV box I had installed a minimal Debian system installed and added the debian-multimedia.org repository for MythTV, this worked very well and the install was quite straightforward. I also added hellion.org.uk repositories for ivtv modules (this provided the drivers for the Hauppauge PVR card).

I’m not sure if I’ve mentioned it but my MythTV box will be backend and frontend in one server. Ideally I would like to have the backend else where and the frontend as a quiet small PC behind the TV but the location of the cable TV port in the wall and not wanting to run cables around the house means that the backend needs to be behind the TV as well.

While I like the idea of installing or building the software yourself, it sometimes becomes awkward if the system gets broken and someone else in the household wants to use it. Also this system will be the only way of viewing digital cable TV as we only get the one chip card from Ziggo (our cable TV company) which will be in the MythTV system so it needs to be a reliable system.

Mythbuntu seems to be a very up to date and reliable system. A friend has stated that is seems to work ‘out of the box’ with the DVB-C and CA/CI module when used with Ziggo and posts like this show that the VDPAU support of the nvidia ION chipset working great as well. Plus it is built on the latest 9.10 Ubuntu.

I think I will go with Mythbuntu to start with and do a complete install of frontend and backed on my new hardware when it arrives. My first delivery is here, just waiting for the second which will hopefully be the next day or two.

With everything decided on I have finally ordered all my parts. Here is the final parts list arranged by where I have ordered it from:

From Mini-ITX.com:

Case – Morex Cubid 2755

Motherboard – Point of View ION-MB330-1 Dual Core 1.6GHz Atom

2GB RAM  – 2GB DDR2

From Alternate.nl:

1TB Harddrive – Western Digital Caviar Green

Tuner – KNC One TV-Station DVB-C

CI Module – KNC One Cineview CI Module

CA Module – Alphacrypt

I am assuming the assembly of parts won’t be too difficult so the next thing to concentrate on is the software. It’s going to be MythTV but whether to install it myself on Debian like I did before or to use something like Mythbuntu will be the decision.

One thing that I hadn’t put much thought into was the harddrive for my MythTV box but a friend mentioned that these ‘green’ Caviar driver from Western Digital. They seem ideal in that they are quiet and also pull less power but of course, what size to get? It seems the 1TB uses slightly less power than the 1.5TB and I think that will be enough storage for now.

The other thing to consider when building a HTPC is the case. Since I first started using mini-itx boards the choice has grown considerably and a lot depends of course on your needs and desires.

There are some very nice cases which try and blend in with normal hi-fi equipment like this one that is reviewed at Tweaktown.

Of course I have certain requirements, one is for the whole system to be as  quiet as possible as it will be in the lounge behind the TV.  For this I prefer cases that use an external power brick similar to laptops. This saves on one more fan inside the case. The power needs of the Intel Atom ION motherboards are quite undemanding so the low-wattage of the power brick style PSUs are very suitable.

The other thing that I am looking for in a case is space for 2 internal PCI cards or one PCI card and an extra 3.5″ bay. This is for the tuner card and it’s CI module buddy which can either sit in a spare PCI slot or an external facing 3.5″ bay.

The cases I am looking at are the Cubid 2755 and 2799 at mini-itx.com, they look very similar so it might just come down to availability.

They seem very compact but tick all the right boxes, they measure less than 30cm square and less than 7cm high. They also have the ability to install a slimline CD player but I don’t plan to bother with that.

Nearly there…..