Dear Min1,
The message means, that the debugger is not reaching the debug components on the target. If the own setup is not working, then I would suggest first trying one of the official demo scripts, in this case the script:
DO ~~/demo/arm/hardware/imx6/sabrelite/imx6quad_smp_sieve_sram.cmm
The script first connects to core 0, then wakes up the other cores and opens an SMP debug session for all cores.
In the case the script is also showing a bus error, then let's check the JTAG connection by scanning the daisy chain of your target:
AREA.view
SYStem.Option TRST OFF
SYStem.Option EnReset OFF
SYStem.DETECT DaisyChain
What is shown in the AREA window?
Best Regards,
Steffen.
