ARMv8 Writing and reading to/from Debug Data Transfer Register

Hello,

I am working on ARM-Cortex-M and i am trying to get the values currently stored in registers <Xt>. To test this, i want to write a random value to X3 and attempt a read.

As i understand, this should be possible by performing the following operations:

• MOV X3, #0x100000000
• MSR DBGDTRTX_EL0, X3
• Read the 'DBGDTRTX_EL0, Debug Data Transfer Register, Transmit' debug register at offset 0x08C

However doing this i do not see the expected data, is this process correct?