the speed of usb msc with softdevice present is very slow

[William.wei]

hi support team,

i tested the example of \\nRF5_SDK_16\examples\peripheral\usbd_msc , and SD card interface , that with the APP_SDCARD_FREQ_INIT 268435456 (1 M) and APP_SDCARD_FREQ_DATA 2147483648 (8M)in SDK config.h file , this example works fine, it takes about 12 seconds to open the disk and see the content of SDcard.

but if i merge this example to ble central,i have to change setting as APP_SDCARD_FREQ_INIT 268435456 (1 M) and APP_SDCARD_FREQ_DATA 268435456(1 M, also 2 M is fine), the disk can be accessed by usb interface, but the speed is very slow, it takes about 1 minute to open the disk and see the content of SDcard.

for other APP_SDCARD_FREQ_INIT and APP_SDCARD_FREQ_DATA settings, combined project can not work normally.

and you give me some advice on this?

 

Thank you in advance!

[Jared]

Hi,

My guess is that it's due to Softdevice operations having higher priorities and it's a matter of scheduling tasks. I think this is acceptable behavior

regards

Jared