Mighty

I tried to post this in the Series II Interior, etc forum, but I don't appear to have permissions for that.

I'm about to pull the trigger and get a Parrot Smart. I plan on hooking up the steering wheel controls to the Parrot, and installing a OBDS2 module and running Torque or something similar on the head unit.

My question: Would an RxDuino be able to work alongside those, to drive the dash top display? Or, do the wheel controls and OBDS need to be dedicated to the RxDuino?

Has anyone given any thought to building a simpler interface device to drive the display that's controlled from an Android device? Maybe one of the guys who has messed with the display can share their thoughts on doing that? (I've skimmed portions of the RxDuino thread, but haven't yet looked to see how much detail he went into about driving the display.) If I can get a little help on the hardware, I'd be able to handle the programming.

On another subject, I thought I'd read that I need some special wiring to hook up the a/c controls? Currently, on Amazon, the Metra product lists only the double-din housing, and specifies that it comes without a wiring harness. Where can I get that harness?

Finally, do I lose cruise control with an aftermarket head unit?

I'd appreciate any advice.

Thanks,

Drake Christensen

paimon.soror

iTrader: (15)

Although you can use the RxD along side an OBD2 reader, I wouldn't recommend it. I have the OBDLinkMX and unfortunately the RxD gets trumped by the messaging frequency of the OBDLink. Although the RxD has logic in it to only display responses that match the parameter it asked for, there are times that the messages get "lost" due to the OBDLink.

You dont need a special harness for the S2 to get AC working

You will not lose CC functionality by swapping head units

It would be difficult to incorporate a remote interface for the screen on the S2 only because it clears itself out if no messages are on the bus. That means that whatever message you send to the screen only displays for 3 seconds before it blanks out. You would have to constantly send the message which makes the task a bit more difficult.

Mighty

I think I'm following you.

I'm just curious how they physically share the port? Does one pass through to the other?

So, with the RxD, you're simply updating the display often enough that it doesn't disappear? For example, I was watching your progress videos, and you display some static text. Do you have a timer or some other trigger to resend that text repeatedly?

Since that's the way the display works, for the simple interface I envision, one of the options I'd put in would be whether or not to automagically refresh the display to retain the information, or to allow that message to age off.

After watching your video, it was unclear to me how the clock and a/c info is getting to the display. Is your RxD providing that information? Or, are those portions of the display still being driven by the car? IOW, are you updating only the text in the middle of the display?

I've seen some messages on the board about the temp only going up to 70 and the clock disappearing. Are those issues that would be handled by the simple interface box? Do they fall out pretty naturally, once you start talking to the display?

I'll go check your development thread again, but in case it's not there, do you have links to documentation on these kinds of questions? I'm sure you don't want to sit here and type up a great big tutorial for me

Thanks,

Drake

Mighty

And now that I've read further into the thread, I see that you had exactly the same idea that I did: Put a little drinking straw into the data stream in Torque and show it on the dash display. In addition, I'd possibly like the option to emulate some of the functionality of the default system to display radio station/music info in that space.

Basically, as much as possible, I want to pull the smarts out of the Arduino package and coordinate everything in the Parrot Smart.

Drake

paimon.soror

iTrader: (15)

I have a Y splitter for the OBD2 port that I purchased to test out the functionality of the RxD with other devices plugged in

That is correct, the message has to be sent on the bus repeatedly to give the impression that it is 'static'

The clock is on its own CAN address, same with the AC. Once you plug in the AC, it sends a message to the CAN letting the network know that it is online. The address that it sends its messages to is the right side of the screen.

The ambient temp sensor is also on its own address, and the clock/radio as well. It gets a bit confusing here because the clock logic is actually built into the screen ... the radio simply initializes it by sending a message to its address.

The middle of the screen is a separate endpoint that can be manipulated without affecting the rest of the screen

This only happens when you put a non oem radio in. the RxD will remedy this. Alternatively, I have a DIY available that will show you how to create an OBD2 adapter for the OEM radio so that you can just plug it in to set the clock then remove.

Mighty

Thanks for the summary.

Do the OBDS monitoring devices ack the messages? Or, does the system just raise the lines, so that multiple devices can read them? I saw a mention of requesting a code. Are the two devices stomping on each other? Or, is it more likely that the two are causing the line to droop enough to miss the signal?

paimon.soror

iTrader: (15)

you are going to need to read up on the CANBUS messaging protocol. There is no acknowledgement built into CAN messaging. It is the responsibility of endpoints to listen for messages directed to them, and they respond back. They dont care who sent it or who receives it.

Mighty

I read the Wikipedia entry on it. I'd never heard of a protocol like this. Very clever.

So, you had to write the code to actually implement the protocol yourself? Or, did you use the one of the existing CANBUS Shield libraries?

I've started searching around for people using the Arduino to write to the CANBUS. Maybe I can learn enough to actually do this.

paimon.soror

iTrader: (15)

because the RxDuino uses MCP2515 for canbus communications, I had to develop my own libraries (which are open source)

https://github.com/paimonsoror/Arduino_MCP2515

Mighty

While this looks like a fun project, I just have too many unfinished projects lying around the house, right now. The ramp-up on the hardware side would probably stretch this out indefinitely. After pondering on this some more, I'm thinking your RxDuino would probably be the best solution for me. What are the chances of another group buy sometime in the near future?

I appreciate your patience with me, and all the time you've given me on this.

Drake