Hi, Elvis,
As you know that the DSC have on-chip program flash, program RAM, data flash(optional) and data RAM.
In practice, user can copy code from program flash to program RAM and execute code in program RAM. I do not think user can copy code to data RAM and execute code in data RAM.
For example, when the DSC has only one block of program flash, it is recommended to copy the code to erase/program flash to program RAM and execute the code to erase/program program flash in program RAM.
You can check the code of flash bean if you develop code in Processor Expert.
Hope it can help you