Monday, September 26, 2011

WT-32 Bluegiga..

Hooked up the WT-32 Bluegiga breakout from Sparkfun and got it working sorta. Paired it with my phone and got A2DP with autoconnect working. Verified analog audio comes out.

Sadly it only has iWrap 3.0 on it which is missing some of the features I need (AVRCP). Will try and update the firmware to 4.0 this weekend and hopefully get it interfaced to a AVR/Arduino for prototyping.. Or make a small brick...

Wednesday, September 21, 2011

The next project..

I liked my iPod. But my Android phone with bluetooth and a subsonic backend media server kinda made it irrelevant.

So it's time to bring the iPod adapter into the new world.

I have two ideas:

Integrated Bluetooth A2DP and AVRCP control with the Pontiac G8. Use wheel controls to play/ff/rev a Bluetooth device. Display playing track info on the DIC. I have all the parts, just need to spend some time putting them all together.

Cemublue - Yep. Take the E&C bus cassette emulator and bring it into the bluetooth world. Should be almost easier then the G8/GMLan solution!

Have decided on using a bluegiga WL-32 module as the bluetooth core. Will update with progress (I hope there is progress!)

Tuesday, August 2, 2011

Monday, March 21, 2011

Cassette Emulation Board - Work in progress

Folks,

The Cemu board as published needs a code revision and 2 mod wires to work. Took quite a bit of head scratching to figure out the issues. Mode wire #1 - the 5V regulator is not grounded. Mod wire #2 - one of the audio paths is not connected to the 3.5mm plug. Code change - the ec_tx and ec_rx are swapped.

Will post new code and board/eagle files this week. With that said, it is working like a charm now.

Thursday, March 17, 2011

Been a month..

And that's about the time it takes batchPCB to turn around a board. I got my 4 prototype PCBs last night, stuffed one of them and made up a wiring harness with a factory Delphi connector ordered from Mouser.

Tonight I plug it in and test it I hope. Good thing the Camaro headunit is about the easiest headunit in the world to remove!

I'll take some pictures tonight.

Thursday, February 17, 2011

CEMU AUX V0.1 Files

I have a breadboarded version of my GM E and C cassette emulator running in my Camaro. Here are all my design files. Consider them free as in beer open source, NOT FOR COMMERCIAL USE without my expressed written permission.

Grab the eagle file to see how I was interfacing with the E&C and the AVRs.

Use them at your own risk as always. Your mileage may vary.

Arduino Casette emulator and E&C Scanner
Cemu Attiny 85 Source code (GCC Compatible)
Eagle Files for Beta Aux in board - Eagle and Schematic
Collection of E&C Logs and messages

I will have a spare board or two if your interested in trying this in you older GM automobile. Drop me a line.

Thursday, January 27, 2011

E and C Cassette Deck emulation

I got it working, I'll post some arduino sketches this weekend.

Have one that emulates and one I have been using as an E&C scanner.

Next step is PCB design. Might port the design from Atmega328/Arduino to Attiny85 or something.

Not bad, 4 days from getting the cassette deck to working emulation!

Friday, January 21, 2011

E&C Head Unit logs

So far, everything I have seen from a 97 CD UNO Chevy Camaro head unit on the E&C Bus. Protocol looks pretty easy to replicate and I think I should have no issues emulating a cassette deck.


Radio On:
1100001011111110010101
Radio Off:
1100001011111110000100

User keypress or sync or something. Happens after most user key presses:
111001101111                                                                

Cassette Deck Poll?:
1110011100000100                       

CD Transition:
111001101110001101
1100001011111110010101 (Confirm this?)
111001101110001101

Cold Start. 12V applied
1101010100                                                                  
111001101111                                                                 
111001101111                                                                
1100001011111111                                                            
1110011100000100                       
1110011100000100                       
1110011100000100                       
11100111000100                         
1100001011111110000100                 
1110011100000100                       
111001101111

Powering Radio on
111001101111
1100001011111110010101
111001101111

Powering Radio Off
111001101111
1100001011111110000100

Most key press events
111001101111


Aux with no CD (Think this is the look for tape deck command. Will confirm when I get one)
1110011100000100

Inserting a CD
111001101110001101
1100001011111110010101
111001101110001101

Ejecting CD
111001101111

Remove Ignition
111001101111
11000010111111100100

Power on by Ignition
1110011100000100
111001101111
1100001011111110010101
111001101111

Thursday, January 20, 2011

E and C bus decoding progress

So far so good. I have the arduino reading E&C. I have observed about 5 or 6 messages. Simple stuff so far. Waiting for the cassette deck so I can progress further.

My data seems to match the link below, at least for radio on and off events.

I will document my progress once I get some ambition. I have a proof of concept and some working arduino code to show for my efforts tonight and that's more than I expected.

Wednesday, January 19, 2011

E&C Bus... Anybody?

New hack on an old bus.. E&C.

I'd like to make an aux adapter for all of us with in dash CD UNO head units in our 90s era GM cars. As some of you know, the UNO single CD player can't control a changer and the aux adapters emulate a changer. So no go.

I hacked an adapter out of a remote cassette deck a few years ago and now I plan on hacking the E&C protocol that controls that... Emulate the cassette deck via AVR/arduino.

Anybody out there have anything on E&C?

So far this is what I have to go on: http://pangea.stanford.edu/~schmitt/e_and_c_bus/