I need some help guys. Which way should I rewire a serial cable ( RS232 ) to be able to link up into the ALDL to monitor the diagnostics. Im using a USB to Serial Cable for the hack job. The ECM is a 7156. Thanks guyz.

Which one for the job? 1 or 2

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Neither.

While only marginally better than the ones you have pictured the "two transistor cable" seems to be more reliable, that is more reliable when connected to a native serial port and not a USB to serial converter.

Most people that have only USB available end up getting a USB ALDL cable, like the Moates.net ALDU1.

 

I agree on purchasing a Moates USB cable, but that $80 figure is a bit stiff for my budget, especially since college is around the corner, I cant spend too much of the money saved for my books and tuition. Sux. The web is full of great info, except info pertaining to a homebuilt USB-Serial-ADLD cable.

 

There are a couple USB to ALDL cable designs that are said to be successful, but only a couple people have made and used them thus far. I know one of the designs was posted here, I think it was saar that posted it.

 

Sweet! Thanks for the heads up bro.

 

I just looked at your other thread and if that's the same USB to serial cable that I have, and it looks identical, then it's flaky at best.

You'll get frustrated trying to use it, and end up buying the Moates cable, if the other USB designs don't work out.

I have a two transistor cable that I tried using with the USB to serial converter with very limited success. I now use that same two transistor cable on my test bench plugged into a proper serial port on my PC.

 

I would go with #2 as it eliminates the need for external power. As for resistor R3, I don't believe that it is required for the 160 baud data stream. Most (all?) GM ECMs that transmit at 160 baud do so continuously.

And the 10K resistor across A & B will change how the ECM controls the engine.

The '7165 ECM is capable of 8192 baud data. But need a two transistor, or better, a MAX232 type interface. The 10K is used to get the ECM into 8192 mode, it is then removed.

Note the 4.7 uf caps, with today's MAX232 devices they can be 1 uf and even .1 uf. So grab the data sheet for the device you get and see what is required.

RBob.

 

MAX232 is FTW.

this is the "board level" view i generatedin autoCAD to aid me in assembly. it's pretty cramped, but i did arrange it all so it would take up the least amount of space possible.

i use 2.2uF caps with no issues. i believe maxim's recommendations were between 1.0 and 3.3uF.

 

Uuuhhh? hhhhm. Well with all the confusion that this thread has caused, seems like the $80 moates ALDL may be my best option. Damn! I thought this homemade cable was gonna be a walk in the park. I guessed wrong. Well Saar, you definitely got the smarts for the job. Ill leave this for the electronic tech savvy pro's. Thanks for replying to my thread Saar.

 

I can tell you my experience.

Have buildt 40-50 2-trans cables, see my homepage for schematics and pictures.
They worked good, but one cable that never let me down was a "MAX232"...

But since moates (and others) offer cheap and good cables its not worth the time and hassle of building your own...

Buy from moates!

 

It is the MAX202 that uses the .1 uf caps. Same pin out and functionality of the MAX232.

RBob.

 

was thinking about it, a TTL/UART to USB converter would make for an extremely simple schematic, no?

 

thats what im about to do right now. I got a few 10k resistors and a transister.

 

YEAHHHHH!!!!!!!!!!!! IT WORKED!!!!!!!!!!!
But only with WinALDL. I tried to load TunerPro RT but it wouldnt work. I clicked on Intitialize Emulation Hardware button but it wouldnt connect. I also tried looking for a option that allows the user to change ports but I couldnt find it. Any suggestions guys?

 

In TunerPro RT, the "Initialize Emulation Hardware" is for... well... emulation hardware, such as the Ostrich 2.0 from Moates, that goes in place of the EPROM.

What you want to set up is Data Acquisition. To set up the ports go to Tools>Prefences>Emulation/Data Acquisition.

You will also need to load a proper ADX for your application so that Tuner Pro can communicate with the vehicle.

 

Aha. Thanks so much for the help Six-Shooter. Quick response, like how it should be. What is an ADX? Is it the 32B file type for my 7165 ECM?

 

No, it's a file that interprets the datastream. You should be able to find it on the Tuner Pro downloads page.

What I think you're referring to would be more similar to an XDF.

 

Cant find the dang dang files. I saw them 2 days ago. But now Im suffering a brain fart.

 

Okay. I found out why there where no log files in the main installation folder. I first had to check for compatibility since the WinALDL was made for XP. Im running WIndows 7. So I ran a compatibility check and made the install with XP compatibility settings. Once the program is installed, I have to open up the program with "Administrator" rights. Then I'm able to log and record in real time along with the file now being saved in the installation folder.

 

here's a question: check what COM port you have emulating when the cable is plugged in, see if it matches TP settings.

EDIT: maybe not, just saw you're using a different laptop now.