Touch Screen Data Bus

2002TLSNavi · 04-06-2004, 7:09 PM

Over two years in the making, I've finally started on my touchscreen interface project. Haven't really gotten very far, but I did manage to hook up an osciloscope to the touchscreens databus. According to the Helms, the data bus is differential. I hooked the scope's ground to the negative side, and the probe to the positive side (scope probe's ground is floating from earth ground).

I set the scope to auto trigger, and pressed the menu button (the physical button, not on the touchscreen).

These images are what came over the bus. The first image is the entire data exchange, the others are zoomed into various parts of the first.

I'm not quite sure what to make of this just yet. It doesn't look like any signalling that I am familiar with (I was hoping for RS485 or CAN). If anyone has any ideas, please share them.

Dave
dave@morecaffeine.net

This ad is not displayed to registered or logged-in members.
Register your free account today and become a member on Acurazine!

ou sig · 04-06-2004, 10:03 PM

Ummmm May I ask what exactly you are doing?

2002TLSNavi · 04-06-2004, 10:52 PM

Quote:

Ummmm May I ask what exactly you are doing?

Well, my goal is to hook up a computer. Have the computer output video to the nav screen, and also be able to use the touchscreen to interact with the computer. I'm envisioning an mp3 player, dvd player, cell phone interface, OBD interface, really the possibilities are endless.

I just need to figure out how the screen up front talks to the nav box in the trunk.

ou sig · 04-07-2004, 12:30 AM

oh hell ya that sounds great!, I have always wanted to be able to get my winamp on my screen or something like that. So you got my support

moreace · 04-07-2004, 11:09 AM

Save yourself oodles of time
work a little extra in teh time you would have spent in it
buy avelectronics box and hook computer up though it

shawhite · 04-07-2004, 11:44 AM

but the avelectronics box will not alow him to control the computer via the touch screen... i believe that is his whole intention in doing it..

moreace · 04-07-2004, 11:52 AM

oh, sorry
well best of luck
keep us informed

2002TLSNavi · 04-08-2004, 8:38 AM

Well, I haven't made much progress myself, however I did find an interesting thread on clubtsx:

http://www.clubtsx.com/bbs/showthread.php?t=2994

tsxer took some scope pictures, and they apear to be the same as what I've got....

2002TLSNavi · 04-09-2004, 10:33 PM

Just thought I'd share the site that gave me the inspiration to start working on this project again....

This guy did a really nice job.... Check it out....

http://www.mujmac.cz/art/hw/tatra_mac_eng.html

2002TLSNavi · 10-12-2004, 7:00 PM

I've found out a little bit more about GA-NET II. Someone was kind enought to point out to me that GA-NET II was really a protocol developed by NEC, IE Bus. Here is the chip that is used in the Nav Units:

http://www.necel.com/partic/function...s/d72042b.html

About 6 months ago myself and a friend of mine had hooked up a data recorder to the Data Bus on his car and recored a bunch of data. We were never able to make much sense of it untill it was pointed out that it was really IEBus. I wrote a quick program to churn through the recorded data and decode the data packets. A good portion of it seems to make sense to me now. I can tell what button or touchscreen location was pressed. Unfortunately I can't seem to get my hands on those NEC chips (they are sold by NEC automotive group in japan and I don't know where to order them from, I spoke to an NEC rep in the US but haven't had any luck so far).

I am probably going to try to design my own decoder chip in programmable logic one of these days when I have some more time.

Just wanted to share this since I haven't been able to find any information about GA-NET II on the web anywhere.

If anyone needs any more information or would like a copy of my data captures and decoder program feel free to email me at dave@morecaffeine.net

Dave

JPritch · 10-12-2004, 8:01 PM

Austin519 on AW.com was hooking up a computer to his car. Not sure if it's as complex as your job, but you could always contact him for some pointers if he has any.

04-06-2004, 10:03 PM	#2
ou sig Boomer SOONER Trader Rating: (0) Join Date: Jul 2003 Location: McKinney, TX Age: 27 Posts: 3,698	Ummmm May I ask what exactly you are doing? __________________ '99 DEP TL w/NAVI Mods TSX Rims - Tanabe NF210 springs - Tokico Blue struts - Chrome shift plate - Acura DVD Navigation - Stone Headers NGK IX Iridium plugs - No intake resonator w/ K&N filter - Outlaw Thermoblock Spacers - Grounding Kit System Alpine CDA-7995 2 JL Audio 12W3V2 subs Focal Polyglass 165V2 Components Kicker KX800.4 - mains Kicker KX600.1 - subs Stinger HPM wire & Bullet series RCA's Stinger HPM Digital 1 F. Cap Dynamat Extreme Optima Yellow Top

04-07-2004, 11:09 AM	#5
moreace Anthracite Trend Setter Trader Rating: (0) Join Date: Aug 2003 Location: Boston, MA Posts: 1,188	Save yourself oodles of time work a little extra in teh time you would have spent in it buy avelectronics box and hook computer up though it __________________ Anthracite/ Quartz/ auto/ nav

04-07-2004, 11:52 AM	#7
moreace Anthracite Trend Setter Trader Rating: (0) Join Date: Aug 2003 Location: Boston, MA Posts: 1,188	oh, sorry well best of luck keep us informed __________________ Anthracite/ Quartz/ auto/ nav

04-07-2004, 12:30 AM	#4
ou sig Boomer SOONER Trader Rating: (0) Join Date: Jul 2003 Location: McKinney, TX Age: 27 Posts: 3,698	oh hell ya that sounds great!, I have always wanted to be able to get my winamp on my screen or something like that. So you got my support

04-07-2004, 11:44 AM	#6
shawhite Registered Member Trader Rating: (0) Join Date: Sep 2001 Location: Jax, FL Posts: 1,154	but the avelectronics box will not alow him to control the computer via the touch screen... i believe that is his whole intention in doing it..

04-08-2004, 8:38 AM	#8
2002TLSNavi Registered Member Trader Rating: (0) Join Date: Feb 2002 Location: NJ Age: 31 Posts: 120	Well, I haven't made much progress myself, however I did find an interesting thread on clubtsx: http://www.clubtsx.com/bbs/showthread.php?t=2994 tsxer took some scope pictures, and they apear to be the same as what I've got....

04-09-2004, 10:33 PM	#9
2002TLSNavi Registered Member Trader Rating: (0) Join Date: Feb 2002 Location: NJ Age: 31 Posts: 120	Just thought I'd share the site that gave me the inspiration to start working on this project again.... This guy did a really nice job.... Check it out.... http://www.mujmac.cz/art/hw/tatra_mac_eng.html

10-12-2004, 7:00 PM	#10
2002TLSNavi Registered Member Trader Rating: (0) Join Date: Feb 2002 Location: NJ Age: 31 Posts: 120	I've found out a little bit more about GA-NET II. Someone was kind enought to point out to me that GA-NET II was really a protocol developed by NEC, IE Bus. Here is the chip that is used in the Nav Units: http://www.necel.com/partic/function...s/d72042b.html About 6 months ago myself and a friend of mine had hooked up a data recorder to the Data Bus on his car and recored a bunch of data. We were never able to make much sense of it untill it was pointed out that it was really IEBus. I wrote a quick program to churn through the recorded data and decode the data packets. A good portion of it seems to make sense to me now. I can tell what button or touchscreen location was pressed. Unfortunately I can't seem to get my hands on those NEC chips (they are sold by NEC automotive group in japan and I don't know where to order them from, I spoke to an NEC rep in the US but haven't had any luck so far). I am probably going to try to design my own decoder chip in programmable logic one of these days when I have some more time. Just wanted to share this since I haven't been able to find any information about GA-NET II on the web anywhere. If anyone needs any more information or would like a copy of my data captures and decoder program feel free to email me at dave@morecaffeine.net Dave

10-12-2004, 8:01 PM	#11
JPritch All Hail the Chief Trader Rating: (0) Join Date: Feb 2002 Location: Lynchburg, VA Age: 31 Posts: 1,686	Austin519 on AW.com was hooking up a computer to his car. Not sure if it's as complex as your job, but you could always contact him for some pointers if he has any.