STR912FAW46X6 Boot up problem

Development Boards MicroMod
1

Hello,

We are doing some development work using an STR912FAW46X6 and are facing a problem. The symptoms are best described as:

  1. Our board does not automatically start executing code upon power-up

  2. The same code does execute on the IAR dev. board

  3. We are unable to attach to a process running after power-up. Says “Unable to Halt Arm9 Core”

Some further info:

  1. Code executes when instructed to through debugger

  2. J-Link can be unplugged while code running and it will continue to run ok until STR9 reset or power cycled

  3. Reset line pulled high using 10K resistor. 0.1uF cap also present on line.

  4. 25MHz Clock confirmed to be present.

  5. Power and ground confirmed on all applicable pins.

Any words of wisdom will be appreciated.

Thanks

Nirosh

2

Have you already tried to download the latest j-link drivers on www.segger.com and the latest embedded workbench by www.iar.com? :?:

Where is located the code?

If it’s in an external memory try to see if there’s a jumper to enable it.

3

Yes, we have the latest drivers now.

The code is in Bank0 and we have verified using jlinkstr91x.exe that the part is supposed to boot from bank0. We are using the internal flash on the 1MB version of the STR912.

Thanks

Nirosh

4

Nirosh

The STR91x can be a bit temperamental, but it may also be that your project is not linked as you expect - eg. is the debug version running from RAM?

We have a reference SW on the following page which you may like to try out to exclude SW problems.

http://www.utasker.com/software/software.html

There is also a tutorial with some programming tips here:

http://www.utasker.com/docs/STR91XF/uTa … TR91XF.PDF

On-line demo at http://demo.utasker.com

We found that the best way to program it is using CAPS (from ST) and the Raisonance debugger (from their low cost development kit). Debugging with IAR/J-Link is fairly good, although breakpoints in FLASH very restricted (not IAR’s fault but the chip supports only 2).

Last point. If you are using early chips there are quiet a few bugs and it is not advisable to run at over 48MHz when working with the debugger.

Regards

Mark

http://www.uTasker.com

5

Hi!

Thanks for the the reply. Actually, we figured out what it was. If there is capacitance on the reset_out pin, the part does not start up.

We have a device which has a built in 0.1uF on this line…which is what caused it not to start up…

Weird…but true…

Nirosh