QUAD SPI External Memory Performance nRF52840

RE: QUAD SPI External Memory Performance nRF52840

Kenneth — Thu, 25 Jun 2020 12:18:49 GMT

Hi Alan,

What I am saying is that the nRF52840 should have no problem to handle the data in terms of sampling them and writing them through a serial interface (e.g. QSPI). The actual time the 3rd party flash memory require to write to flash is beyond our control. Good starting points for development would be:

https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.0/qspi_example.html

https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.0/app_sdcard_example.html

https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.0/lib_sdcard.html

We do not have any detailed numbers here, conceptually your application should work.

Best regards,
Kenneth

RE: QUAD SPI External Memory Performance nRF52840

alanm — Thu, 25 Jun 2020 09:54:31 GMT

Hi Kenneth - please keep me right here - if I understand correctly you are saying that 5ms is enough time for the flash memory to complete its write of the data?
- Can I also ask you, is this the fastest way for a nRF52840 to write to external memory? If not what would be the fastest? And correct me if I am wrong - there doesn't seem to be any sdio and thus eMMC support on these mcu's? Another question - I assume eMMC over sdio would be faster if it was available but an not sure if I am correct - can you tell me?

Thanks in advance
Alan

RE: QUAD SPI External Memory Performance nRF52840

Kenneth — Wed, 24 Jun 2020 10:58:26 GMT

Hi,

I do not see any reason why this shouldn't work. You will have 5ms here between each new polling, this is plenty of time. I guess you could even buffer up some data before writing to QSPI also if you wanted.

Best regards,
Kenneth