Saving Data to NRF52840 then Writing to SD card.

RE: Saving Data to NRF52840 then Writing to SD card.

Vidar Berg — Tue, 31 Jan 2023 19:23:48 GMT

I agree with what Turbo J said above. I have not profiled the current consumption of writing to internal flash vs. writing to an SD card, but I assume it should be efficient to store it to a SD card as well.

For reference, the internal flash is rated to last 10 000 write/erase cycles, see Absolute maximum ratings. This applies to each 4K flash page.

RE: Saving Data to NRF52840 then Writing to SD card.

wellmacj — Tue, 31 Jan 2023 16:39:06 GMT

got it i'll check out buffering the data in the RAM, and also focus on writing in smaller amounts less than 16 KB. got it. Thank you for the response.

RE: Saving Data to NRF52840 then Writing to SD card.

Turbo J — Tue, 31 Jan 2023 16:36:30 GMT

The program flash inside the NRF5280 does not like to be written to too often, much less than an SD card.

Try buffering a decent amount of data in RAM, then write to card.

Warning: When you write 16KB at once to the card, it may not turn back to low power mode on its own. Reading or writing a single sector fixes that behavior IIRC.