Hey guys I just figured out an ultra cheap way to make a USB ALDL cable. Go to Ebay and look for the nokia ca-42 cable. I picked one up for $3 dollars with drivers included on ebay several months ago to fix a broken hardrive of mine, when I read about the DIY serial aldl cable that gave me the idea. This is actually a cell phone cable however it changes the usb to a rs232, Cut of the end of the cable where the phone plug is an expose the wires. There should be five small wires -- you only need to use two wires. The white one is ground, the red is rx 5volt. Thats is you now own a $3 dollar ALDL cable.

Does tunerpro recognize it as a valid aldl cable?

interesting idea.. search for usb ttl and cables come up with wires already exposed and circuit boards.. The ecm transmits a different signal than rs232 like the serial port on older computers which is why we use transistor data cables to convert it.. the usb has another converter on top of that for the serial signal.. unless its a max232 chip i think.

but those cables on ebay say they take a TTL signal hmm they look like china copies of the max chip.. i might have to buy one to try too..

I don't see why they would go through the trouble to convert the PC USB to RS-232 and use that at the phone end when no one will be using 100 meters of cable to download their stuff. RS-232 was designed for somewhat long distance data transfer. A phone would be close by the PC so I would think that it is USB to TTL. The only thing is that it is more than likely 3.3v TTL and not 5v TTL. The ECM should still see the high of 3.3v because it usually a 2.4v min. for a high.

For $3 it is worth a try if you can figure out how to set the signaling rate to the odd-ball ECM ALDL rate.

I looked into it a little. It looks like the CA-42 is USB powered so that is good. The phone side is 0 - 3.3v TTL so that is good, but will it handle the ECM sending the 5v high to the USB cable? The protocol is RS232 so that is good. Looks like a winner if you can get it to do the 8192 data rate. Slap an ALDL connector on the other end and charge $60-$100 like the vendors do.

The only potential problem is the ECM sends 5v TTL to the 3.3V TTL USB cable. It may or may not have a chip that is 5v tolerant. At worst you may need voltage limiting / dividing. A 20K and 40K ohm voltage divider would probably keep it happy.

hmm.... what IC does it use to convert RS232 to USB? the FTDI chips are the only ones i've ever used that reliably worked at 8192...

Along with 57.6Kb, 115+Kb and so on. Which is why they are used on EBL products. They cost more, but they work. The fact that they work is more important then the cost...

RBob.

did anyone actually tests this out and confirm if it works or not?

I did get it to work with a 6299 ecm, however as Rbob said reliability is a factor. The adapter I received worked great it's a chinese FTDI clone, I was lucky enough to select a good one, there's so many on ebay I remember when I was looking it was overwhelming. Anyway that being said I think it's really best to purchase a high quality ALDL cable, buying the chinese stuff off ebay is a gamble.