XM-Ready head unit software integration?

**TaZMaNiaK** · 02-03-2005, 11:06 PM

This is maybe a longshot, but I've been thinking about my XM Direct installation, and I have a question (after this brief schpiel). You can hook an XM Direct to your computer with a standard RS-232 serial interface, and software like TimeTrax, Frodo, MMC, and all the others will read the serial data from the unit (gives you the channel list/artist/title), and send serial commands to the unit (channel up/down, direct channel entry/presets). Before I started on my quest for a carputer, I bought a Pioneer DEH-P6500 head unit with the Pioneer GEX-P903XM tuner (which I have very recently upgraded to an XM Direct with the Smart Digital Adapter). I have grown to like the head unit, and the fact that it has the artist/title display, and my steering wheel remote. This brings me to my question:

Since the head connects to the Smart Digital Adapter for the Direct over the IP Bus, and the SDA translates the IP Bus signals to standard RS-232 protocol to interface with the Direct, (and the SDA's are available for almost every XM Ready head out there), has anyone thought of making a plugin or something for any of the front-ends that will allow the computer to interface with head units (via the SDA - no matter what brand head you are using, the SDA adapts it to the same interface), and allow it to display the title/artist/channel of whatever is playing through the front-end (not necessarily just XM, could be MP3, DVD, AM/FM station, whatever - there's actually 4 fields available), and also accept commands from the head unit, like channel up/down and presets. Channel up/down would operate depending on the currently selected function in the front-end, like prev/next track, tune +/-, etc. Presets could do just about anything.. Say, #1 will change the current function, and 2-6 would be actual presets. Something like that. The SDA also has the RCA inputs, so you wouldn't need a separate input adapter, FM Mod, or tape adapter.

Now, why you ask? I say why not.. There's times where I wouldn't want the screen to be on, but still be able to change the station through the stereo. IMHO, with more and more gadgets in the car, it is getting very dangerous out there, and the ability to use my steering wheel remote to do things I'd otherwise have to reach (and look) over to do makes things that much safer, for me if nobody else.

What do you think?

Matt

**SWC** · 02-04-2005, 07:06 PM

Don't know about the head unit control, but you can use the pioneer steering wheel remote with the irman.

**GizmoQ** · 02-05-2005, 07:18 PM

Originally Posted by TaZMaNiaK

VERBOSE MODE OFF

What do you think?

Matt

I am currently watching a thread on XMFAN that's working on something close to what you're talking about. There are several of us with the XM Commander and Carputers. We have one guy working on a splitter that allows us to have both commander head unit and PC hooked-up to the rcvr can at the same time. So far we know that the recieve side, i.e., channel data to cmdr/PC can coexist, but the xmit side (commands to rcvr can i.e., channel change, mute etc) must be isolated from each other. For me, that's no problem, DPDT manual switch in line on two xmit wires - I only need commander head unit in control when computer is left at home for short trips in town.

We were going to investigate using the commander as a separate LCD for the Carputer later. But now that you mention it, I may propose your request.

ALSO SEE: XMDirect Cable

Possible to split XM Direct cable to computer and XM commander?

**frodobaggins** · 02-05-2005, 07:55 PM

Well hell, I guess my "secret" project is out.

**TaZMaNiaK** · 02-06-2005, 02:17 AM

See, what I was thinking of is connecting COM1 to the XM Direct, and COM2 to the head unit (or Commander display, now that you mention it - that would work the same way). That way there's no switching - the head unit always displays what is playing, and the computer always reponds to the head unit's commands; and the XMDirect is always connected and ready. The software plugin would take care of deciding what data goes to what COM port. Like I said, it would be standard RS-232 data output, and the SDA would take care of translating it for whichever brand head unit you have. Something like this should work with a USB to Serial adapter if necessary, since they just make a virtual COM port. Since we already know how to make the XMDirect talk to the computer, why can't we make the computer talk to the head unit via the same data link?
Could you post a link to that thread on XMFan, or PM it to me if that's not allowed? I tried to find it without success.. I'd really like to follow that too.

Sorry if I rooned something, Frodo.. Great minds think alike, what can I say?

**mgithens** · 02-07-2005, 04:45 PM

Originally Posted by GizmoQ

I am currently watching a thread on XMFAN that's working on something close to what you're talking about. There are several of us with the XM Commander and Carputers. We have one guy working on a splitter that allows us to have both commander head unit and PC hooked-up to the rcvr can at the same time. So far we know that the recieve side, i.e., channel data to cmdr/PC can coexist, but the xmit side (commands to rcvr can i.e., channel change, mute etc) must be isolated from each other. For me, that's no problem, DPDT manual switch in line on two xmit wires - I only need commander head unit in control when computer is left at home for short trips in town.

We were going to investigate using the commander as a separate LCD for the Carputer later. But now that you mention it, I may propose your request.

ALSO SEE: XMDirect Cable

Possible to split XM Direct cable to computer and XM commander?

does the deck recognize the unit when using the toggle switch idea?? seems like you would need to reset the deck to get it to recognize... I could be wrong, but maybe I am misunderstanding...

I moved my XMD unit from Pbus to serial this week and it is cool, but last night it was mid-20s and the computer wouldn't boot... so no computer, no mp3, just left with FM (bleh) and cd's (but who carries those things)... anything that could make this work would be great...

**bridqer** · 02-07-2005, 11:54 PM

I bought an old mac printer A/B switch so I could switch control of the XMD between HU and PC. I was thinking about connecting the transmit(or would that be the recieve) wires together so that both would display the information no matter which one was in control.

**TaZMaNiaK** · 02-09-2005, 01:29 AM

Well, like was said before, connecting the TX line from the XMD to the RX lines of the HU and PC should work to get both to display the info. However, the issue is controlling the XMD from both sources. As GizmoQ suggested, a simple switch to select which TX line the XMD sees (while isolating them from each other) should work, but what I am suggesting is for the head unit to be connected to one COM port, the XMD connected to another, with a software plugin to feed display info and commands between the two and to the front-end itself. This would not only allow both the HU and XMD to be connected and functional at the same time, but also for the HU to control the front-end software (with the channel up/down buttons and presets) and display non-XM data from it as well, such as MP3 title/artist, AM/FM band (from Radiator), DivX movie title, etc. You would just leave the HU in XM mode all the time.

As far as the HU interface cable, assuming the original SDA to XMD cable is straight through, that means the TX/RX swap is in the jack pinout of the SDA, and we would just make the same cable as for the XMD to PC, just swapping pins 1 & 2 on the DIN-8 connector, or pins 2 & 3 on the DB-9 connector. If you have a separate 12V supply for the XMD (not running off your power supply, or you are using the Commander unit), and you have to remove the carputer, you can still connect the two DB-9's together with a lesbian connector, and it would still let you control the XMD directly from the HU.

BTW, I still can't find that thread on XMFan.. Little help?