How to use the functions ux_system_initialize about cache_safe_VOID *cache_safe_memory_pool_start, ULONG cache_safe_memory_size

[andy817501]

i have open the dcahe and setted it, but i I don't know How to provide a pointer, and the Cache how to use in usbx

[ayedm1]

Hi @andy817501, You can this example from NXP

https://github.com/nxp-mcuxpresso/mcux-sdk-examples/blob/fc18ff0c12ba90fe71714eaa4244717efa18c61c/evkmimxrt1040/azure_rtos_examples/usbx_host_hid_mouse/board_setup.c#L89

`

ifndef USBX_MEMORY_SIZE

define USBX_MEMORY_SIZE (60 * 1024)

endif

ifndef USBX_MEMORY_CACHESAFE_SIZE

define USBX_MEMORY_CACHESAFE_SIZE (60 * 1024)

endif

ULONG usb_memory[USBX_MEMORY_SIZE / sizeof(ULONG)]; AT_NONCACHEABLE_SECTION_ALIGN(char usb_memory_cachesafe[USBX_MEMORY_CACHESAFE_SIZE], 64);

ux_system_initialize((VOID *)usb_memory, USBX_MEMORY_SIZE,
                     usb_memory_cachesafe, USBX_MEMORY_CACHESAFE_SIZE);`

`

[andy817501]

Thank you for your help

[andy817501]

你好@andy817501， 你可以从 NXP 获得这个例子

https://github.com/nxp-mcuxpresso/mcux-sdk-examples/blob/fc18ff0c12ba90fe71714eaa4244717efa18c61c/evkmimxrt1040/azure_rtos_examples/usbx_host_hid_mouse/board_setup.c#L89

` #如果定义 USBX_MEMORY_SIZE #定义 USBX_MEMORY_SIZE (60 * 1024) #结束

如果定义 USBX_MEMORY_CACHESAFE_SIZE #定义 USBX_MEMORY_CACHESAFE_SIZE (60 * 1024) #结束

ULONG usb_memory[USBX_MEMORY_SIZE / sizeof(ULONG)]; AT_NONCACHEABLE_SECTION_ALIGN(char usb_memory_cachesafe[USBX_MEMORY_CACHESAFE_SIZE], 64);

ux_system_initialize((VOID *)usb_memory, USBX_MEMORY_SIZE,
                     usb_memory_cachesafe, USBX_MEMORY_CACHESAFE_SIZE);`

`

I would like to ask if there are any precautions to be taken with USBX if I want to use DMA