JTAG vs Serial Wire

[christopher]

Posted on May 13, 2013 at 19:46

I'm using the STM32F407 in a new design and due to a conflict of peripheral pin assignments (Why isnt there more clk pin assignment flexibility?) I cannot use the JTDO pin of the device for JTAG. I think my only option is to use SWJ, which I have never done. I'd like to know what the tradeoffs are and if I need different programming hardware (Other than ST-Link/V2) and anything else I may need to know. I have to go straight to production hardware manufacture with this.

Thanks

[jj2]

Posted on May 17, 2013 at 21:36

''I need my questions answered specifically.''

Pardon - perhaps if you'd then ask w/some specifics - such would be supplied...  4K7 - 10K have been used by our group, multiple clients - appear to work well. ''Either the internal ones work or they dont.''  I bow to your superior knowledge & MCU experience.  (if you read with some comprehension - our experience teaches - despite your ''wish/hope'' - that such is not at all times - under all conditions - the case!) Leave to others the pleasure of further ''appreciative'' discourse...

[blackwierd]

Posted on October 07, 2013 at 15:19

I'm trying to figure out how to make a jtag circute for a STM cortex M4.

Where would i find a document describing which pins can be used for JTAG /SWD ?

[Tesla DeLorean]

Posted on October 07, 2013 at 17:26

ARM has a lot of documentation.

ST has pin level documentation for the STM32 parts in the Data Sheet/Manual for each of the specific devices. Review some eval board schematics to understand some workable wiring configurations.

[Uwe Bonnes]

Posted on October 08, 2013 at 08:33 With JTAG you can do Board tests as you can take over the STM32 pins. SWD  accesses the CPU.