# Problem
Place the registers in their appropriate categories.
# Process
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# Answer
* General purpose.
* `r0`, `r2`, `r5`, `r12`.
* Special purpose.
* `LR` - Link Register.
* `PC` - Program Counter.
* `PSR` - Program Status Counter.
* `SP` - Stack Pointer.
* Special purpose but not user accessible.
* `MAR` - Memory Address Register.
* `MDR` - Memory Data Register.
* `IR` - Instruction Register.
* Uncategorized (fake).
* `AND` - Accessible Non-Data.
* `DUD` - Data Used Daily.
* `NOR` - Non Operating Register.