Sorry all for the late replies, I was on holiday
Quote: Originally Posted by mox
Argh, you beat me there by one day! I've just finished doing the same SPDIF hack to my HU tonight
. I guess your Scenic has a VDO "Tuner List" HU too, right?
Yes, the damn "no-aux" Tuner List
Quote:
- You are keeping the changer connected to enable the HU's SPDIF input. Does this mean you always have one or more CDs inserted? AFAIK, an empty changer is automatically ignored and skipped by the HU when switching audio sources. This is why I bought an aux interface from connects2.com (type VRNX001). It acts as a fake cdchanger and also contains an analog-to-SPDIF encoder.
Yes, I've seen it, but I really think it's not worth the 100 EUR or so, that are mostly due to the Analog>SPDIF converter I don't need. So you're right, I always have a few CDRs in the changer : It's definitely cheaper
and the only drawback is that every 80 minutes, the SPDIF is muted during a few seconds while the changer loads a new CD. This would probably disappear if I'd only put 1 CD in the changer but I don't really care for now.
A big advantage of my setup is that I have a simple DPDT relay that switches the SPDIF input from the changer to the PC once the PC is started, so if I don't start the PC or if I remove it from the car for maintenance, the setup is transparent and the changer is fully functional
. Of course, it only works if you have a cd-changer...
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- Furthermore, how can I get the audio line-in (and the mic input) of the epia to be mixed into the SPDIF output? I haven't tried much yet (nor did I search..) -- all i noticed is that I couldn't hear anything from both inputs. Neither of them is muted in the mixer panel and they are being output properly to the ANALOG line out.
Well, I have no use for that right now, but indeed, I think "line-in to line-out" is a kind of "shortcut" that doesn't go through the SPDIF encoder. As you say, it would suffice to go through a higher level application that would just sample these inputs and pass them through to the "wave out" to have them go "the long way" and via the spdif encoder. In that case, the "Playing" mixer settings would of course have no effect, but the "Recording" ones would. Probably using any realtime processing effect with all settings at zero would do the trick, using "some" CPU (depending on how well the effect is written)...
It shouldn't be too hard to write one, but I don't have time or need for that right now.
Maybe another way would be through a virtual sound driver such as the one included in TotalRecorder...
Quote:
Anyway, congrats on a hack well done. I am pondering a smart PIC-processor based interface so I can use the HU's stalk control to send commands to the PC. The stalk control in my Clio is actually a simple 3x3 matrix of switches. I am quite sure the Scenic is identical.
Mmmh, don't know, but if I were you - and that's in my low-priority plans - I'd purely and simply try to emulate the control protocol of the CD changer...
Regarding that, the status of my research is that among the protocols listed on
http://www.mictronics.de/?page=cdc_proto , the only one that uses asynchronous two wires transfer (RX + TX + no clock) is the Blaupunkt one. Moreover it uses the same wires as our Tuner List, so that's encouraging : compare the last page of
http://www.blaupunktusa.com/NR/rdonl...5E/0/MDP01.pdf to the attached pinout of the Tuner List (taken from
this post). I also had confirmation by bistie on planeterenault.com forums that once the levels are adapted (5V TTL to 12V RS232) the protocol is compatible with a PC serial port. Still have to investigate exactly the protocol grammar, but that would allow not only next/previous/pause but also cd change *plus* feedback of CD#/track# to the dashboard. If you're ready to use a PIC, I think this path is simpler and worth the try, isn't it ?
Vicne.