Renault "Tuner List" Head Unit/CD changer hacking - Controls - Page 27

pippolippi · 03-13-2006, 06:40 AM

Quote: Originally Posted by Vicne

Also, don't you think of using a DC/DC converter (car adapter for your laptop) instead of the inverter which probably introduces lots noise due to hashing ? OTOH, they're often rather expensive...

Yes, that's the problem: the price. Not that I wouldn't spend the money if it was my laptop, but it is not my laptop (as it is not my car, everything is the property of my company).
Besides the car adapter would be specific to it, while the inverter, albeit much less elegant and efficient, it's useful (in theory) with other laptops (if/when they give me another one) and other devices.

Vicne · 03-13-2006, 07:29 AM

Quote: Originally Posted by pippolippi

Yes, that's the problem: the price. Not that I wouldn't spend the money if it was my laptop, but it is not my laptop (as it is not my car, everything is the property of my company).

I see.
Well, it doesn't have to be your adapter, couldn't it be theirs too

?

Quote:

Besides the car adapter would be specific to it, while the inverter, albeit much less elegant and efficient, it's useful (in theory) with other laptops (if/when they give me another one) and other devices.

Sure...

peppuz79 · 03-13-2006, 08:24 AM

Hi,

the 'piggy HU tester' :

HU
13 <---- /\/\/\ 10 kohm -----> 2
14 <-----/\/\/\10 kohm ------> 3
15 <--------------------------->5

I've tested with the both version of the software and working fine, but ONLY the booting frame can be received from the HU .
It's good for testing HU or for the people that don't want anything else.

Bye
Peppe

Vicne · 03-13-2006, 08:51 AM

Quote: Originally Posted by peppuz79

the 'piggy HU tester' :

HU
13 <---- /\/\/\ 10 kohm -----> 2
14 <-----/\/\/\10 kohm ------> 3
15 <--------------------------->5

I've tested with the both version of the software and working fine, but ONLY the booting frame can be received from the HU .
It's good for testing HU or for the people that don't want anything else.

Well, I'm not sure of your goal...

What we called the "BOOTING" frame is generated by the emulator and goes to the HU...
The simple 10K resistor is known to work for reading signals coming from the HU, but as far as I know it doesn't work the other way, to send signals to the HU, because of the HU's internal pull-up.

Once again, maybe don't understand what you want to achieve...

peppuz79 · 03-13-2006, 09:20 AM

Quote: Originally Posted by Vicne

What we called the "BOOTING" frame is generated by the emulator and goes to the HU...

of course

Quote: Originally Posted by Vicne

The simple 10K resistor is known to work for reading signals coming from the HU, but as far as I know it doesn't work the other way, to send signals to the HU, because of the HU's internal pull-up.

sorry error in cut&paste :

3 <---> 14

Quote: Originally Posted by Vicne

]
Once again, maybe don't understand what you want to achieve...

you can use this interface only to see in dashboard "Tr 1 CD 1" and listen the music from some SPDIF source.

right?
pep

Vicne · 03-13-2006, 09:47 AM

Quote: Originally Posted by peppuz79

sorry error in cut&paste :

3 <---> 14

you can use this interface only to see in dashboard "Tr 1 CD 1" and listen the music from some SPDIF source.

Oh, you mean you tested without a resistor there and it works ?

So for the moment you win the "simplest interface" contest with a "1-resistor" circuit. You can only be beaten if we can get rid of the 10k resistor altogether - which could be the case btw... Wanna give it a try ?

What I don't undestand is that it seems to activate the SPDIF in, but you say only the booting frame can be received and I don't understand why. If the circuit is OK for this frame, it should be ok for others too, shouldn't it ?

pippolippi · 03-13-2006, 10:04 AM

Quote: Originally Posted by Vicne

Well, it doesn't have to be your adapter, couldn't it be theirs too

?

I'll have to find a very convincing excuse, I just cannot justify it saying that I can work in the car while commuting, can I?

(I usually have mains supply available when I need the laptop for work use).

Vicne · 03-13-2006, 10:12 AM

Well it depends on your boss. You could try :
- I need access to navigation programs to get to work earlier when there are traffic jams. It's either an adapter or a Tomtom
- When I'm on the way back, it's a good time to charge the PC so I can continue to work at home (cause I don't have mains supply at home, the house is only lit with candles)
- I think there's a new market the company should be involved in. It's called "carpeecee". Never heard of it ?

pippolippi · 03-13-2006, 10:30 AM

Quote: Originally Posted by Vicne

Well it depends on your boss. You could try :
- I need access to navigation programs to get to work earlier when there are traffic jams. It's either an adapter or a Tomtom

This isn't going to work, since it's a 2km commute

Quote:

- When I'm on the way back, it's a good time to charge the PC so I can continue to work at home (cause I don't have mains supply at home, the house is only lit with candles)

Mmmh, my boss lives nearby, so he know this isn't true. He also know that I'll never work from home

Quote:

- I think there's a new market the company should be involved in. It's called "carpeecee". Never heard of it ?

This is the most suitable excuse, after all he asked me to setup internet access at the office when everybody else either didn't know what it was or though it was a passing fad. But it's too far away from our line of business.

Vicne · 03-13-2006, 11:27 AM

Quote: Originally Posted by pippolippi

This isn't going to work [...]

Then sorry for you

.
Maybe find an adapter on eBay or "hope" it's the serial adapter which is defective - which wouldn't surprise me...

pippolippi · 03-13-2006, 01:11 PM

Quote: Originally Posted by Vicne

Maybe find an adapter on eBay or "hope" it's the serial adapter which is defective - which wouldn't surprise me...

Yes, it's the serial adapter. With another one there's no such problem. The one that's working has a screened cable while the one with the problem has a plain cable, no screen.

pippolippi · 03-13-2006, 01:15 PM

Quote: Originally Posted by pippolippi

I think that "simpler is better" (on the same principle I'll see if I can simplify further the optocoupler interface, I think that I can do away with at least the transistor from the HU).

Well, that wasn't a good idea, since not only it doesn't work, but while rewiring the circuit to revert it the previous, working, one, I made a mistake and blew the transistor. I hope it's just the transistor and not the hu

Edit: the mistake was that I connected the collector directly to 12V, bypassing the 680ohm resistor.

Vicne · 03-13-2006, 04:34 PM

Quote: Originally Posted by pippolippi

Well, that wasn't a good idea, since not only it doesn't work, but while rewiring the circuit to revert it the previous, working, one, I made a mistake and blew the transistor. I hope it's just the transistor and not the hu

Edit: the mistake was that I connected the collector directly to 12V, bypassing the 680ohm resistor.

Hot hot hot

Well, I hope the transistor played a fuse role and the HU is not damaged...

Vicne · 03-14-2006, 03:00 AM

Quote: Originally Posted by Vicne

- CD change buttons are now handled correctly.

I noticed yesterday that I have a rather strange behaviour upon CD change and I think I know why, partially at least :

- First, after CD has changed, the HU sends a "PLAY" command to start playing the new CD. Unfortunately, Roadrunner (and Winamp BTW) give a toggle behaviour to "PLAY" : first time it begins playback, second time it pauses, third time it starts again, etc. So in our case, the "PLAY" sent after CD change is considered a "PAUSE". Then you have to press PAUSE twice to restore the correct behaviour (fortunately, Roadrunner and Winamp don't consider "PAUSE" as a toggle). So unless I find a non-ambiguous way to "PLAY" (that would have no effect if already playing), I'll have to filter out this "PLAY after CD CHANGE" (as well as the "NEXT after RANDOM ON" mentioned by Pippolippi)

- Second, sometimes, a CD change seems to lock things up. HU doesn't send commands anymore and I have to switch the HU OFF and back ON to restore the correct behaviour. I'm suspecting it's because I currently send the 18 frames that normally follow a CD change request in a single burst. Maybe I should send the first 15, then wait for the "PLAY" command before sending the last 3 ones... (see rosetta stone)

Apart from that, I'm rather happy with my tests. I'll concentrate on finishing the hardware this week...

pippolippi · 03-14-2006, 03:43 AM

Quote: Originally Posted by Vicne

- Second, sometimes, a CD change seems to lock things up. HU doesn't send commands anymore and I have to switch the HU OFF and back ON to restore the correct behaviour. I'm suspecting it's because I currently send the 18 frames that normally follow a CD change request in a single burst. Maybe I should send the first 15, then wait for the "PLAY" command before sending the last 3 ones... (see rosetta stone)

Though I didn't perform extensive testing, I didn't notice any problem upon cd change. But then I'm just sending the "I'm playing" frame, I don't try to simulate the cd changer real sequence.