Renault "Tuner List" Head Unit/CD changer hacking - Controls

**slimmegane** · 03-02-2006, 04:41 AM

Originally Posted by Vicne

Sorry, not sure I understand your question.

What I mean is that SPDIF and Serial Port are completely independant :
- You can first wire the serial port, MAX chip, transistor, etc to pins 13 and 14, start the software, then the head unit, and check that you can then change source to CD changer and see the head unit display "TR1 CD1"
- If that works, then you can wire pins 18/19 to a SPDIF source and check that it works too and that you can hear sound through the Head Unit.

Oh, thanks a lot, now is more clear

I will try soon as possible.

**peppuz79** · 03-02-2006, 08:54 AM

http://focus.ti.com/lit/ds/symlink/pcm2902.pdf

PCM2902 (only 02 the 00 series no SPDIF) also used for headphones from the USB port but now i see that support conversion from analog to digital (spdif).

What do you think about this DAC?

pep
p.s. also tried AK5340 but poor result..

**Vicne** · 03-02-2006, 10:00 AM

I have no experience but googling around shows interesing results such as this project and this thread.
It might be a very interesting device, providing both analog input (for use as a stand alone device) and USB input (for use as a PC interface for PC's that don't have SPDIF out)...
Only thing that scares me is soldering SMD components by hand...

Edit : Bad review : "This circuit 2902 is bull **** [...] I will not recommand this circuit, for the spdif to USb interface netheir as ADC to USB". Although, we would use it the opposite way USB > SPDIF or ADC > SPDIF instead...

**peppuz79** · 03-02-2006, 10:27 AM

Originally Posted by Vicne

Only thing that scares me is soldering SMD components by hand...

me too :-(

I've found this 2902 (3 pieces) in my old DVD player (broken of course) one of these is directly linked (with the usual caps) in the SPDIF plug, the other one works like RCA Analog Input and the last one like RCA ANALOG output, and everything works without any USB connection (perhaps some emulation??).

pep

**Vicne** · 03-02-2006, 10:51 AM

Originally Posted by peppuz79

me too :-(

I've found this 2902 (3 pieces) in my old DVD player (broken of course) one of these is directly linked (with the usual caps) in the SPDIF plug, the other one works like RCA Analog Input and the last one like RCA ANALOG output, and everything works without any USB connection (perhaps some emulation??).

Oh, yes, I admit I hadn't read the spec fully. It looks more like a anyhting-to-USB + USB-to-anything chip than a anything-to-anything, and it clearly states "To get the appropriate operation, one of the following operating systems must be working on the host PC...". So it won't work as a simple standalone Analog>SPDIF
As for your DVD, maybe it had a linux kernel inside... it has been reported as working with Linux on the discussion thread mentioned above.

**peppuz79** · 03-02-2006, 11:17 AM

Originally Posted by Vicne

As for your DVD, maybe it had a linux kernel inside... it has been reported as working with Linux on the discussion thread mentioned above.

No kernel inside, it's controlled by an atmel MCU (+512Kbyts EEPROM) with some buffer, mpeg2 decoder, ide controller (for the dvd) and pcm2902 for output/input signal.

if it had been a kernel linux inside, I would have already used it.

:-)
pep

**Vicne** · 03-02-2006, 11:30 AM

Originally Posted by peppuz79

No kernel inside, it's controlled by an atmel MCU (+512Kbyts EEPROM) with some buffer, mpeg2 decoder, ide controller (for the dvd) and pcm2902 for output/input signal.

No idea then...

if it had been a kernel linux inside, I would have already used it.
:-)

:-)

**pippolippi** · 03-02-2006, 12:36 PM

Originally Posted by peppuz79

http://focus.ti.com/lit/ds/symlink/pcm2902.pdf

PCM2902 (only 02 the 00 series no SPDIF) also used for headphones from the USB port but now i see that support conversion from analog to digital (spdif).

What do you think about this DAC?

If you're after an usb->spdif adapter (like me), I bet you could find a complete one cheaper than the cost of the components.

**Vicne** · 03-02-2006, 01:06 PM

Originally Posted by pippolippi

If you're after an usb->spdif adapter (like me), I bet you could find a complete one cheaper than the cost of the components.

I just ordered 2 free samples at ti.com. Can you beat that ? :-)

**pippolippi** · 03-02-2006, 02:46 PM

Originally Posted by Vicne

I just ordered 2 free samples at ti.com. Can you beat that ? :-)

Factor in the case, the connector, the circuit board, other passive components and the time.
A local chain has an usb sound card for 10€ (actually 9.99, VAT included), I'm not sure it has spdif output but I'd be very surprised if it hasn't.
However, does anybody qualifies for free samples?

(I don't want to register only to find that I don't)
Edit: ok, bugmenot to the rescue.