Results 1 to 6 of 6

Thread: DIY cable problems

  1. #1
    New Member
    Join Date
    Sep 2010
    Posts
    1

    Default DIY cable problems

    Does anyone know if the schematic from Tech Edge, using the MAX 232 is correct. I read in a post someone had mentioned that diode D3 was incorrect.
    I built the circuit as shown in their schematic, and I was using EFILive V4 to try and connect to my 1989 5.7L IROC-Z.
    I have connected the Tech-Edge circuit to the ALDL connector via home built cable, and the Tech-Edge circuit through a Serial to USB adapter cable made by Prolific Corp. to a Toshiba laptop.
    I can't get it to connect ?
    Any help would be great !

    Aliman
    Here is what I'm seeing when I try and connect

    1:12.035: Initialising...
    21:12.597: Opening COM3 8228,8,N,1
    21:12.718: Ready.
    21:18.632: Check vehicle interface...
    21:18.639: Waiting for Aldl bus silence of at least 50ms...
    21:18.687: Requesting Max232 interface to acknowlege: $FF,$55,$AC...
    21:18.796: Com timeout: Expecting frame header byte
    21:18.800: No response from Max232
    21:18.800: Retrying Max232 detection...

    21:18.800: Waiting for Aldl bus silence of at least 50ms...
    21:18.847: Requesting Max232 interface to acknowlege: $FF,$55,$AC...
    21:18.956: Com timeout: Expecting frame header byte
    21:18.962: No response from Max232
    21:18.962: Retrying Max232 detection...

    21:18.962: Waiting for Aldl bus silence of at least 50ms...
    21:19.011: Requesting Max232 interface to acknowlege: $FF,$55,$AC...
    21:19.120: Com timeout: Expecting frame header byte
    21:19.126: No response from Max232
    21:19.126: Retrying Max232 detection...

    21:19.126: Interface cannot be detected

    21:19.153: Scanning for heartbeat and chatter frames...
    21:19.153: Waiting for Aldl bus silence of at least 50ms...
    21:19.303: Com timeout: Expecting frame header byte
    21:19.307: No chatter found
    Last edited by aliman; September 26th, 2010 at 01:40 AM. Reason: Added info

  2. #2
    New Member
    Join Date
    Nov 2010
    Posts
    3

    Default

    check the com port number for usb to serial adapter , it should be the same as efilive software

  3. #3
    Joe (Moderator) joecar's Avatar
    Join Date
    Apr 2003
    Posts
    28,403

    Default

    Hi Ahmed, welcome to the forum

    What vehicle do you have...?

  4. #4
    New Member
    Join Date
    Nov 2010
    Posts
    3

    Default

    hi joecar
    i've honda civic 93

  5. #5
    EFILive Developer Site Admin Blacky's Avatar
    Join Date
    Mar 2003
    Posts
    9,490

    Default

    Most USB-Serial adapters are not capable of generating the correct baud rate required for ALDL communications. The baud rate required in 8192 baud. A Real PC UART chip controlling a real RS232 serial port is capable of generating a baud rate of 8228 which is close enough to 8192 to allow it to work. I recommend using a real serial port, you may need to get your desktop computer (if it has a serial port) close to your vehicle to test whether the cable works using a real serial port. If it does then you can be pretty confident that the Serial-USB converter is not generating the correct baud rate.

    Regards
    Paul
    Before asking for help, please read this.

  6. #6
    New Member
    Join Date
    Nov 2010
    Posts
    3

    Default

    Hi Blacky
    the usb to serial converter works good and the Tech Edge circuit is correct
    I had made it and used it with usb to serial converter and everything is good
    now i'm making a circuit to connect aldl to usb directly

Similar Threads

  1. Flash Scan box to usb cable connection problems
    By cmitchell17 in forum FlashScan V1
    Replies: 6
    Last Post: July 3rd, 2009, 03:17 AM
  2. why do I have a com cable and what to do now?
    By C5Vette in forum FlashScan V2
    Replies: 0
    Last Post: July 4th, 2008, 10:14 AM
  3. Custom/DIY calibration definition file?
    By jimter in forum General (Diesel)
    Replies: 5
    Last Post: October 10th, 2007, 08:25 AM
  4. TTi Stage 1 Question/DIY Tuning
    By lplott in forum General (Petrol, Gas, Ethanol)
    Replies: 8
    Last Post: August 19th, 2005, 02:00 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •