fatfs with nrf_block_dev_qspi sleep behavior

[nealjack]

Hello,

I'm currently using fatfs with a QSPI flash device on an nRF52840 with SDK 16. I was wondering what is the best way to put the qspi device to sleep in between reads/rights?

If I leave the fatfs filesystem mounted and the block device initialized, my device draws 600uA continuously. If I unmount and uninitialize the block device before sleeping, and reinitialize when I need to write/read from my flash, I achieve my expected sleep current for my system of around 15uA. However, unmounting and uninitializing seems like a fairly heavyweight operation to do frequently after every read and write. Is there a better way to manage QSPI power states that is supported by the nordic port of fatfs, and the block device and qspi libraries?

Thanks for any suggestions!

[Simonr]

Hi

In order to achieve a lower current consumption than 600µA you will have to uninitialize the QSPI driver before going to slep I'm afraid. Please note that you shouldn't have to I.E. configure the memory every time you initialize the QSPI. Do you have to unmount the block device before sleeping?

Best regards,

Simon