When using CCS 6.2.0.00050 to debug a program for a TMS320F28069M in a LAUNCHXL-F28069M noticed that the Variables view was reporting "unknown register 'pl'", rather than the value, for a variable which was in the PL register, which is the "Product Low" register in the C28xx core:
This doesn't prevent debugging but just shows that Variables view doesn't know how to display a variable in one particular C28xx core register.
The project used is attached, which a modified version of a ControlSuite example. 5305.Example_2806xGpioSetup.zip
Edit: The attached example has an bug in the vector_square() function, but such that the bug in my code caused the compiler to allocate the length argument in the PL register which highlighted this issue.