[mythtv-users] 169Time revisited

Michael Chmilar chmilar at acm.org
Tue Aug 1 17:09:25 UTC 2006


The XP machine hosting the r5000hd will talk to a DVHS deck. So, the
goal is to make the MythTV machine appear to be a DVHS deck. There
are two things that the XP machine needs to be satisfied that the
Myth machine is DVHS:

1. The configuration ROM for the firewire port on the Myth machine
(not really a "ROM", since you can alter it!) must say that the Myth
machine is an AV/C device.

2. The XP machine will send some queries using the AV/C protocol,
such as "Are you powered on?", "Do you have a tape inserted?", "Is
the tape a DVHS cassette?", and so on. The Myth machine must respond
with the correct answers.

Once these requirements are satisfied, the r5000hd software will
happily stream the MPEG-2 data over the firewire port.

ddr1394 has a program that sets up the configuration ROM. It also has
a program that does the AV/C chit-chat. However, I found that I had
to modify the responses to make the r5000hd happy.

I have created a modified version of dd1394 which combines the ROM
config and AV/C chatter into one program. I also removed the stream
capture from this program, since I want Myth to perform the capture.

This setup should work with any device that talks to a DVHS deck,
including the 169time.

AVSForum.com has a couple of long threads about the r5000hd
modification. Reading through it, you will find a number of people
who started with 169time, and switched to r5000hd. I don't recall all
of the reasons, but it seems like the 169time was just not reliable.

The r5000hd is extremely reliable.

I am using the r5000hd to record all of the HD channels from Directv,
including HBO-HD, Showtime-HD, HDNet, Universal-HD, TNT-HD, and the
network stations (NBS, CBS, FOX, ABC).

The r5000hd also captures standard definition (SD) channels on
Directv (which the 169time may not be able to do, IIRC). However, I
have been having difficulty getting reliable recordings of SD in
MythTV. The problem is that the r5000hd takes a few seconds to detect
that the stream has changed from HD to SD, and resynchronize. During
this transition, it is not sending a valid MPEG2-TS over firewire,
and this appears to confuse MythTV's firewire capture. I have not
spent much time addressing the SD issue, since my primary interest is
capturing HD. (I have a second SD-only Directv receiver which is
sufficient for my needs.)

Is the r5000hd worth it? It is fairly expensive to get the
modification, and you have the added expense of an XP machine to host
it. However, it is very reliable, and works as advertised.

I should also point out that r5000hd provides a complete set of
XP-based software, including an application to schedule recordings by
date/time (using web browser for program guide). I used the r5000hd
strictly on XP for a year before I embarked on interfacing it with
MythTV. My main complaint in XP world was that I needed to use the
mouse and keyboard all of the time. I much prefer MythTV's interface.

On XP, the r5000hd is now integrated into SageTV, as well. SageTV
offers some similar features to MythTV such as client/server
machines. I have never tried SageTV, so I can't compare it to MythTV.

These XP setups allow you avoid having a separate machine acting as
an intermediary.

I am happy to share my hacked-up software (modified ddr1394 and
channel-changing script) with anyone who wants to use them. Both are
small enough that I can email them.


--- Mario Limonciello <mario.mailing at gmail.com> wrote:

> Michael,
> 
> I realize now that post was a bit old.  For some reason I read 2002
> as 2006
> :).
> 
> I emailed Dan Dennedy about this and he was also mentioning
> ddr1394.  He
> said it is a bit rough around the edges, but said that it could be
> hacked
> together to something functional if I took some time with it. 
> Which
> firewire config ROM are you speaking of when you say AV/C
> capability needs
> to be enabled? Have you uploaded these patches to modify ddr1394 to
> svn of
> linux1394?
> 
> Do you actually use the r5000hd as a recording source for all of
> your
> programming in myth then with this intermediatary XP Box?  Also the
> 169Time
> mod, you say that its not as reliable and robust, is that to be
> taken in a
> literal sense? eg - the box crashes, or streams just dont
> consistently work?
> I'm just kinda curious about this - as I may invest in one or the
> other if
> this is really a feasible working project...  If you do use the
> r5000hd
> often  - how is perfomance?  Would you call it a worthwhile
> investement?
> 
> I appreciate the info,
> 
> On 7/31/06, Michael Chmilar <chmilar at acm.org> wrote:
> >
> >
> > --- Mario Limonciello <mario.mailing at gmail.com> wrote:
> >
> > > So anyone on the list actually have a 169Time mod done?  Would
> you
> > > care to
> > > experiment with linux1394 svn to see if you can grab video?  Or
> > > anyone else
> > > have an opinion about why this shouldn't work?
> >
> > I am using MythTV with an r5000hd mod. This is similar to the
> > 169time, but owners who have used both systems seem to find the
> > r5000hd to be more reliable and robust.
> >
> > The r5000hd requires a Windows XP machine as an intermediary. The
> > r5000hd software on the XP machine can send the MPEG2 TS over
> > firewire to a DVHS deck.
> >
> > It is possible for MythTV to emulate a DVHS deck and capture the
> > stream using the Firewire cable box tuner. These extra pieces are
> > needed:
> >
> > - A modified version of ddr1394 to communicate with the XP
> machine
> > using the AV/C command protocol, and set AV/C capability in the
> > firewire config ROM.
> >
> > - Use plugctl to set up the firewire ports.
> >
> > - An external channel change script talks to the XP machine via
> ssh
> > to change channels.



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