STM32 jtag chaining possible

 STM32 jtag chaining possible

Hi,

do you know if it is possible to use JTAG chaining with the STM32F103xC processors? Are there any specific things a controller have to implement to support jtag chaining?

best regards
Harald

 RE: STM32 jtag chaining possible

Surely, chaining is an inherent part of JTAG - so, if it didn't do chaining, it wouldn't be JTAG...?

 RE: STM32 jtag chaining possible

that means jtag chaining is a part of jtag and every controller who has a jtag interface is also able to support jtag chaining?

ULINK supports device chaining on the JTAG bus. But a JTAG device must have the following attributes to allow chaining:

¦BYPASS register must be implemented for chaining.
¦After reseting TAP the IDCODE must be the default instruction
¦Bit 0 of ID Code must be 1.
¦In CAPTURE-IR state the fixed value 1 must be loaded into the IR.
If the automatic setup does not work, you may manually setup the attributes of the device. In this case only BYPASS register must be implemented for chaining.

http://www.keil.com/support/docs/3245.htm

Every device (also the STM32 devices) will have these features implemented?

 LPC1758 daisy chaining

Hi,

I've tried the jtag daisy chain feature with some LPC1758 devices, and unfortunately it's not working!!!!!!!!!

I can see only one device by keil uvision (lastest version) in the Cortex-M target driver setup. I'm using the ulink2 interface.

I've tried to download a programm to the devices and both of them downloaded this programm and the programm is running. But (of course) I'm not able to debug one of these devices...

Did I forget something important???? Any advice is really appreaciated.

best regards
Harald