Re: [OpenOCD-user] Error: JTAG scan chain interrogation failed: all zeroes

[ravi k. <rav...@gm...>]

sorry sir i didnt get how to reply in in-line format...sorry for the
inconvenience caused from my side.

On Fri, Jun 28, 2019 at 3:07 PM Andreas Fritiofson <
and...@gm...> wrote:

>
>
> On Fri, Jun 28, 2019 at 8:54 AM ravi kiran <rav...@gm...>
> wrote:
>
>> Actually we are able flash and debug  this saml21 board with Atmel
>> ice.But our requirement is to debug hardware through JTag interface.
>> The same Jtag interface is working with sama5d36xplained pro board .But
>> when it comes to saml21 board im facing the above issue.
>>
>>>
> Please explain what you mean by "debug hardware". Everything you can do
> through the NGX + SWD-adapter through OpenOCD, you can also do via the
> on-board cmsis-dap adapter on the Xplained board. What exactly is it you
> think you can do with the NGX?
>
"Please explain what you mean by 'debug hardware ".---->  Here im trying to
check hardware components like lpddr2,nandflash,emmc through openocd
commands(which will directly interact with processor).In target config file
im configuring the addresses of peripherals of micro controlers. After this
i'm  writing the addresses specific to hardware components(like address for
emmc lpddr2 with data )  and i will verify the responses got from openocd
server.


>
> You write as if you think you're trying to use a JTAG interface, you're
> not, you're using an SWD interface. The chip does not speak JTAG. Forget
> JTAG. It's not an option. Using a "JTAG" dongle together with an SWD
> adapter doesn't change that. You cannot do boundary scan or anything like
> that with the SAM L21, if that's what you're trying to do. What you can do
> with the SAM A5D is irrelevant because that chip speaks JTAG as well as
> SWD, the L21 doesn't.
>
In openocd 0.10.0 version they mentioned that openocd supports  for
saml21,samd21 board and even openocd has the config file for saml21 and
samd21 boards.

  Is ther any other option to interface saml21 board with jtag for
debugging(like jtag-swd adapter).

>
> Also, unless you learn to reply inline or at the bottom and keep the list
> in Cc, this will be my last reply to you.
>
> /Andreas
>

"Please explain what you mean by "debug hardware".