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JTAG communication failure !!

roger239955
Associate II
Posted on September 27, 2009 at 07:53

JTAG communication failure !!

4 REPLIES 4
roger239955
Associate II
Posted on May 17, 2011 at 13:23

Hi

I startet examples blinky from KEIL subdirectory Examples\ST\STM32F10xFWLib

an it works fine (With STM3210E-Eval and ULINK-ME)!

Then i start the example I2S\Interrupt but after flashing (Debug)i have

following error (for all examples):

JTAG communication failure !!

Can anybody help me

greetings

Roger

jj
Associate II
Posted on May 17, 2011 at 13:23

Sounds to this reporter that you have inadvertently switched/disabled one/several of the JTAG pins. Review the I2S example to confirm that you've ''turned-off'' JTAG functionality.

If so - you should be able to place mini program into ram (after changing your boot configuration) which restores your JTAG pins. Much earlier in this forum you can find pretty detailed instructions.

Bet you won't do this again! A defensive technique is to always include a small piece of code atop your program which ''restores JTAG functionality'' upon some special GPIO activation (or other controllable action). With such code in place you gain an easier/faster mechanism to restore JTAG...

[ This message was edited by: jj.sprague on 09-09-2009 00:16 ]

tomas23
Associate II
Posted on May 17, 2011 at 13:23

If you have trouble to connect to the board anytime later, check ''Connect under reset'' in the Debug options dialog box.

ibtissemahmed
Associate
Posted on May 17, 2011 at 13:23

Hi,

Since some SPI3/I2S3 pins are shared with JTAG pins (SPI3_NSS/I2S3_WS with JTDI

and SPI3_SCK/I2S3_CK with JTDO), they are not controlled by the I/O controller

and are reserved for JTAG usage (after each Reset).

For this purpose prior to configure the SPI3/I2S3 pins:

- For STM32F10x High-Density devices, the user has to disable the JTAG and use

the SWD interface (when debugging the application), or disable both JTAG/SWD

interfaces (for standalone application).

- For STM32F10x Connectivity-Line devices, the user can use the solution above

(SWD or disable both JTAG and SWD), or it is possible to remap the SPI3 pins

on {PC10, PC11, PC12, PA4} GPIO pins in order to avoid the conflict with JTAG

pins (and it is possible in this case to use JTAG interface). This remap is

used for STM3210C-EVAL evaluation boards in this example.

This is clearly highlighted in the example readme.txt file.

Hopefully this answers your question.

Concerning the ''Connect under reset'' option on Keil toolchain, it allow holding the hardware reset(HW RESET) signal active while connecting to the device. You may use this option when the user program mistakenly disables the JTAG/SW interface.

Regards,

Ibtiss.