James' Tech Blog

Just poking around Chromium pages (you know “Google ChromeOS”) and found some interesting stuff. They have a page about building the OS http://dev.chromium.org/chromium-os/building-chromium-os/portage-based-build First the URL says it all Portage based build. Later in the page they have emerge-<board_name>. Then about ebuilds and their chromium-overlay.

Does it actually use Gentoo? I’m not sure what their overlay has, but it seems like they are using Portage to build and maybe some Gentoo patches along the way. Check out the part about dependencies. It clearly has eselect ebuilds and gentoo-syntax for vim. Also, core-utils with -vanilla USE flag (as in include Gentoo patches). Why use Portage though? Especially since the user already has a working system and can install missing dependencies. Why not use Paludis? Well Google isn’t the only ones to ever use Portage in their project. I believe Openembedded’s bitbake is Portage based also.

Anyways, way to go Gentoo! Helping the world reach a brighter tomorrow!

So I got a Hauppauge HVR 950Q cause Comcast is supposed to be switching to all digital in the very near future. That means my wonderful PVR 500 will become horrible obsolete, though it has served me very well and I wish I would have gotten it sooner. I had made sure that it was supported in Linux before I bought it. It wasn’t horribly difficult to setup, but I’ll add some links here and some tips.

It is a DVB (digital video broadcast) device though it has an analog tuner. A quick look at linuxtv.org shows that it is supported as of kernel 2.6.26. Furthermore, there are nice instructions on their wiki. All I had to do was enable dvb and the xc5000 in the kernel, I made them modules cause then I didn’t have to reboot, extract some firmware and voila! Not! It turns out that the kernel version of the xc5000 I was running complained about the firmware version. Specifically, dmesg was spitting out errors close to:

xc5000: waiting for firmware upload (dvb-fe-xc5000-1.6.114.fw)…

And then complaining that the file could not be found. Bummer, where was I supposed to get firmware 1.6.114? Shouldn’t the linuxtv wiki have a link to the newest firmware? Maybe steventoth has it on his website in the xc5000-untested directory? The answer to all of these is No. Well, except the first one and the answer is: http://www.kernellabs.com/firmware/xc5000/dvb-fe-xc5000-1.6.114.fw Apparently, the guys at Xceive says it’s okay to distribute the binary firmware! Awesome, no more extraction scripts.

Next step, scanning channels and configuring mythtv. Sidenote, my database is still screwed up so I’m still running 0.21, thanks Gentoo! So, I went to their wiki and searched for Comcast. It seems that somebody has hashed all this out already here. Download the scte65scan tool and follow the instructions. Namely, do the scan and look at the output. I had 2 VCT_IDs 3013 and 0. 3013 seems right according to the wiki page and 0 just sounds weird. This should give you an idea of what channels you have available. Next go to schedulesdirect.org and setup a new lineup or edit your current one if you have been using a digital box/analog capture device. Using the output from scte65scan select the correct channels. Now, I could be wrong about the exact order here, but you need to know the sourceid for the new lineup. So, setup the 950Q in mythtv-setup and select your new lineup as the source. Don’t worry about channels we do that next. You need the sourceid because the scte65scan outputs sql code that includes the sourceid so if you set it incorrectly you could screw up your analog channels, from a different “source”.

Drop into mysql:

~# mysql -u mythtv -p

use mythconverg;

select * from videosource;

If you have given your new source a nice name like “comcast-digital” it’s easy to see that the new sourceid=2

Next rerun the scte65scan using your VCTID and -f3,2 because my sourceid=2 if yours is 5 use -f3,5. The README file that comes with scte65scan explains most of this. Oh, right you did “mysqldump -u mythtv -p mythconverg > myth.backup” right? Good. Now we have an sql file that has all of the channel info we need. Following the instructions bring it into your database. That should be it, run mythfilldatabase and all should be well.

I have no problem recording channels, but when I try to “Watch TV” it doesn’t tune. I think it might be that it is trying to tune a frequency that doesn’t have a channel, but I have tried after I recorded something so the frequency should be right. Mythtv kinda remembers what frequency/channel  it was last set to or more likely the hardware is still set to that frequency. Anyway, mplayer can play the dvb stream no problem so I can watch “live-tv”. I guess I’ll save that mystery for another day.

Updated link for 1.6.114 firmware. Thanks Devin!