For complete development and discussion, visit the thread Mojo offered.OverLOAD said:As requested, here's the current state of what we plan to do:
We are developing a customized module, which can plug into the Head Unit (henceforth known as HU), in the place of the Tape module, or MD module. If you currently have either of these modules in your HU, you will need to remove it to put this module in it.
The module, initially will have the following connection points
1 - RS232 Computer serial port
----A. for firmware upgrade
----B. remote control of winamp on a PC via a 'keypad' plug in
2 - 2 pairs (4 total) RCA line-level Audio input connectors
----A. Selectable audio input between the 2 different channels by pushing the PRG button (Say goodbye to mini-stereo, these are close to the same cost, and have a more sturdy connection)
3 - 1 Expansion/Upgrade connector (These will all be later on..)
----See below for more info.
4 - 1 Main connector to the main Head unit.
----A. This is the main connection point we are using to get into the radio.
Here's what you will be able to do:
Intially, when we make a few of these units, we're going for base level functionality. Thus, the software upgradability.
The steering wheel controls will work as per normal operation. The volume controls the built-in amplifiers level, the Up arrow and Down arrow will send the corresponding Next/Last Track control via the serial port to any connected device, in the format the the existing serial keypad plugin is expecting. There is really very little that we need to do here. The RND button will send the control to winamp in a similar manner to enable random mode playback vs. sequential playback.
As already mentioned, the PRG button will switch between RCA inputs 1 and 2.
The unit will 'appear' on the LCD screen to operate exactly like the Tape module, and will display "Tape" when in playback mode.
We plan on including two circuit boards, which one plugs into the connector on the HU, and the other holds the board in place by screwing down where the tape/MD modules would have.
You will then be able to run your RCA cable to the connection point of your choice, with the type of connection that you desire.
I had previously said that we would have an in line pre-amp, to boost signal levels, but after some testing with various devices, we don't have any trouble driving the radio louder than the CD player with the test devices we have connected (IE, there's plenty of gain on the HU to get an adequate volume level).
We are still planning for March to have all of this accomplished, and ready for anyone who might want to buy it. The initial price that was mentioned is very likely, but until we have costed out all of the materials, and tested the preliminary design, we can't say for sure that's what it will be. There may be some sheet metal fabrication that could cause problems. We're looking for alternatives at the moment.
Then, later on down the road, here's the future plans:
The expansion modules. We don't have the time to reverse engineer the IPOD's controls (or other mp3 player ) until we've got this part completed. He're what we're currently considering.
----A. Remote control functionality for MP3 devices. We are currently only planning on making modules for the Archos Jukebox (what we own) and the IPOD. Others may possibly be developed based on demand, difficulty, and cost.
----B. Additional audio input sources such as Optical or Digital SPDIF connector
----C. Video switcher hardware (to synch video with audio)
----D. Hands-free Cell phone connector
LCD display. We currently don't see anything that looks like text being sent to the HU from the Tape module, so it looks like it runs with pre-configured messages. The plan, is to buy/borrow a MP3 CD player, and reverse engineer the bus traffic to determine how to display our own customized text on the screen. This is a fair sized project in of itself, but we definately want to do this before the mp3 player remotes. This will be a firmware update for the device, and be a no-charge upgrade. It will then display "AUX-IN" or some other appropriate text then, and we will try to figure out how we can get song names from WinAmp to the LCD display. This will likely involve writing our own WinAmp plug-in.
Ok.. That's about it. If there's anything else that I left out, I'll edit this post to update it.