Part3_lesson4---coprocessor access instructions

1. What is a coprocessor?

CP15 is a coprocessor,

CP15: System control coprocessor CP15, which provides additional registers for configuration and control of Cache,mmu, protection system, clock mode, and other system items such as size and end operations.

How do I access the CP15 coprocessor?

The registers defined in the CP15 can be accessed to reach the CP15, which can be ordered by the MCR and MRC instructions.

The CP15 defines 16 sets of registers,

You can go to the ARM1176JZFS file's system control processor registers this section to see the information.

Two commands to access the coprocessor MCR and MRC

R represents the universal register, and C represents the coprocessor.

The MCR means to copy the contents of R into C, and the MRC instead.

such as access: Read the main ID register

MRC p15,0,r0,c0,c0,0

Part3_lesson4---coprocessor access instructions