Target multicore configuration wrong in JTAG T32

Question

I am observing below error while attaching a core in JTAG T32,

Target multicore configuration wrong

Selected core position is already in use

Target multicore configuration wrong

Target multicore configuration wrong

Target multicore configuration wrong

Target multicore configuration wrong

Target multicore configuration wrong

I tried restarting the JTAG but still issue still persists.

Does any one has faced same issue and got some resolution against it?

Answer 1

When multiple devices or cores share a JTAG interface they form a looped chain of shift registers. From the debugger's point of view there is on single shift register, and it needs to generate the correct number of TCK cycles to shift all the data into each device.

So somewhere in whatever tool you ar using you must describe the JTAG chain in terms of position of each of device/core in the chain and the width of their respective JTAG shift registers.

It looks likely in this case that you have not configured the JTAG chain for multiple cores, so that every device is described as being in position 1 of the chain.

In the Lauterbach M-Core debugger manual for example, the JTAG chain (the manual calls it a "daisy-chain") is configured via SYStem.CONFIG commands, and it has an example:

^{Ref: https://www2.lauterbach.com/pdf/debugger_mcore.pdf}

The example is perhaps less than clear the commenting terse, but the preceding description of the individual commands is clear enough: