Initialization file + USB TAP -> program exception 0x0700

[duckycool]

Hi all,
    This is my steps below:
    Installed Codewarrior v8.8.
    Created a bare board project and selected my build target - MPC8544.
    Set my initialization file path in CW->Edit->debug version setting->EPPC debugger settings.
    Connected my board through USB TAP with my host PC.
    F7(Make), and F5(Debug).
   
    Then the USB TAP connection bar showed and finished the progress bar, and then it just stop in a windows, the text in the windows said something like" the excutable elf is running ...." but I didn't see
the "Welcome to Codewarrior" printed in the UART.

     So, I used debug->break to break the process, and it just go to a file and stop in __start.
     There is also a message show above that "program exception 0x0700" .......
     
     My question is that is anything wrong with my steps ? Did I miss something I should go through to get
     the "Welcome to CodeWarrior" ??

      If nothing I missed, the procedure is fine, then the second question is why the program exception
      in __start ?? Does it mean the board didn't initialize at all and just stop in the very beginning ?
      Any hint for me to go on to get the Welcome ??

      Thank you

[duckycool]

Hi Tom,

   Sorry for late to update this.

   I just picked up this board again after doing the other projects in the past couple months.

   The UART port of the Host PC I used is very bad.

   I just change another PC which UART is ok then the "hello" just printed.

   So, that's my bad to use a bad Host :~~~

   Thanks Tom.

[duckycool]

Dear Tom,
     There is nothing in the UART port.

     For the demo program, I follow the instructions of "Using Target Initialization Files" of "Pro_&_Linux_App_Edition_Targeting_Manual" to create the bare board project, and the program is to print "Welcome to CodeWarrior" with infinites loop.

     So, you said this program may probably trap on the error exception right?
     When I use Debug->Break, it do jump to the __start and show exception.
     But for this simple demo program, it should not happen with any exception though.....

     Could you help me to confirm couples things,
     (1) I don't have any code in flash, I only use a initialization file running through the CodeWarrior with USB TAP, and it supposed can bring up the board and execute the demo program of a New-Open bare board project which is to printf "Welcome to CodeWarrior" right ??
     (2) Does it mean the initialization file has brought up the board sucessfully when I see the debug elf file is executing? The initialization file should be a work one if the download progress bar finished?
     (3) Will it be different between Linux Edition and Windows Edition ? Cause I using Windows Edition and follow the Linux Edition manual ??
     (4) If the u-boot just somehow in the flash, will it confuse the board bringing up and I should erase it first ?

     Thanks a million for your help.
    


Message Edited by duckycool on 2009-01-23 01:14 AM

Message Edited by duckycool on 2009-01-23 01:17 AM

[J2MEJediMaster]

When the Debugger says the ELF file is executing, either it is running or it has gotten away from the debugger.

To your questions:

1) You don't need Flash to execute the program. It can run in RAM. However, be sure that you pick the project's Debug version build target to ensure that the program is built for and will be downloaded into RAM.

2) If you're getting a download progress bar and that completes without errors, the CPU ought to be initialized properly by the initialization file. I know that there are things you can do with initialization files, but to keep unknowns to a minimum I would not modify the initialization file generated by the IDE.

3) You can't mix and match Linux and Windows debugging operations.

4) I'm assuming from that statement that you're using a PowerPC board that automatically boots into Linux, right? What you have to do is have CodeWarrior and your program ready to go, then start the board. Immediately click on the Debug button in CodeWarrior, so that its intialization file and the CodeWarrior debugger get control of the board before it can boot into Linux.

HTH.

---Tom


Message Edited by J2MEJediMaster on 2009-01-23 11:09 AM

[duckycool · Accepted solution]

Hi Tom,
    Thank you again for your reply.
   
    I'm trying to bring up a customized PowerPC board with a customized initialization file.
    I don't have bootloader and Linux kernel yet.

    Just a very first thing - porting initialization file from MPC8544DS to my customized board.

    So, it sounds like my initialization file is ok, but somehow the UART just don't print......

    I think I should try IIC or GPIO for debugging.
    Will post the result when I figure it out.
    Thanks a lot.

[J2MEJediMaster]

If the program downloads and you get a elf file is running message in the debugger, the program should be executing. If there was something wrong, usually the debugger is going to bring the program up short when it traps on the error exception. How are you viewing the UART's output? For most of these demo programs, it's up to you the write the UART code unless the demo is for a specific evaluation board. Have you tried a different demo program (that doesn't rely on console I/O) to see if you step through that code?

---Tom