InDashPC.org Forum Index InDashPC.org
In Dash Car PC forum
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Decoding message traffic

 
Post new topic   Reply to topic    InDashPC.org Forum Index -> Software
View previous topic :: View next topic  
Author Message
boone711



Joined: 15 Feb 2010
Posts: 1

PostPosted: Mon Feb 15, 2010 3:25 pm    Post subject: Decoding message traffic Reply with quote

I have a question about how the COM port data is being encoded/decoded. When I received an updated chip for my Car2PC adapter, it was left in debug mode (DB1) instead of default (DB0; see Car2PC API on the forums).

In my 2004 Acura TSX w/Nav the interesting thing was that I could see all sorts of traffic even if unrelated directly to the stereo. The first thing I noticed was that user interaction with any of the devices in the car would show up. I could decode a line that updates the volume number and current AC mode (which get sent to the nav screen when either is changed).

The best part was that I could read touchscreen coordinates when pressing the touchscreen. I identified sets of numbers that would go up or down depending on where i pressed on the screen (more to the right would be higher in one set, lower on the screen would be higher in another set, etc).

If I could interpret these lines as they occur I could have basic touchscreen interaction my Car PC. Unfortunately I cannot get the data to show in the same format that it appears in the grom console program. Any time I try to read the data in homebrewed programs, serial port loggers, or hyper terminal, it shows random characters and does not locate the line return characters (etc). I am familiar with ASCII/Hex and have tried all types of methods of reading the COM port data and different encoding but to no avail.

If anybody knows much about the stuff any info would be appreciated. I dont know where to go at this point.

Thanks,

Travis
Back to top
View user's profile Send private message
jbors
Site Admin


Joined: 12 Nov 2004
Posts: 1675

PostPosted: Tue Feb 16, 2010 8:36 am    Post subject: Reply with quote

Basically the RAW data from the bus come in binary form.
You will need to switch hyperterm into Binary mode to get it.
The format as follows:
FF <LEN> 0x43 0x4D <binary data>
Back to top
View user's profile Send private message
Louk
Newbie


Joined: 13 Feb 2010
Posts: 17
Location: Netherlands

PostPosted: Sat May 15, 2010 4:25 pm    Post subject: Reply with quote

jbors wrote:
Basically the RAW data from the bus come in binary form.
You will need to switch hyperterm into Binary mode to get it.
The format as follows:
FF <LEN> 0x43 0x4D <binary data>


Is it also possible to write binary data to the bus?

_________________
Drive on ... :Drive:

Louk.
Back to top
View user's profile Send private message
jbors
Site Admin


Joined: 12 Nov 2004
Posts: 1675

PostPosted: Wed May 19, 2010 10:06 pm    Post subject: Reply with quote

Yes, you have to switch device into PS1 mode.
The CDC emulation will turn off.
Here is the CDC emulation script (may not work work for your car though)



bmw_cdemu.zip
 Description:
BMW CDC emulation for Car2PC

Download
 Filename:  bmw_cdemu.zip
 Filesize:  941 Bytes
 Downloaded:  444 Time(s)

Back to top
View user's profile Send private message
Louk
Newbie


Joined: 13 Feb 2010
Posts: 17
Location: Netherlands

PostPosted: Thu May 20, 2010 1:02 pm    Post subject: Reply with quote

jbors wrote:
Yes, you have to switch device into PS1 mode.
The CDC emulation will turn off.
Here is the CDC emulation script (may not work work for your car though)


Thanks; I will take a look at it this (long) weekend.

_________________
Drive on ... :Drive:

Louk.
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    InDashPC.org Forum Index -> Software All times are GMT - 8 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You can attach files in this forum
You can download files in this forum


Powered by phpBB © 2001, 2005 phpBB Group