Completely disable cache

You probably don’t want to do this because of lower performance (~ 10x) and higher power consumption. That said, this is how you do it:

crt_dir.PNG

The MPLAB XC32 C compiler provides an easy to use cache configuration file: “pic32_init_cache.S” If you copy this file into your local project directory it will override the default runtime setup code used to initialize the cache.

Change the “__PIC32_CACHE_MODE” from
“_CACHE_WRITEBACK_WRITEALLOCATE” to “_CACHE_DISABLE”

You can find this file in the following XC32 install directory:
…xc32/vx.xx/pic32-libs/libpic32/stubs

File: pic32_init_cache.S

/* Cache Coherency Attributes */
#define _CACHE_WRITEBACK_WRITEALLOCATE      3
#define _CACHE_WRITETHROUGH_WRITEALLOCATE   1
#define _CACHE_WRITETHROUGH_NOWRITEALLOCATE 0
#define _CACHE_DISABLE                      2

/* Set __PIC32_CACHE_MODE to the desired coherency attribute */
//#define __PIC32_CACHE_MODE      _CACHE_WRITEBACK_WRITEALLOCATE    //default runtime setup policy
#define __PIC32_CACHE_MODE      _CACHE_DISABLE

Note: “__PIC32_CACHE_MODE” is used to define the KSEG0 cache coherency algorithm bits (K0<2:0>) found in the PIC32MZ’s “CONFIG” register. Please refer to the device data sheet for details.

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