Speed of reading from flash address with nRF52840

[Jay]

Hi everyone,

I was wondering if anyone benchmarked the time for reading a word from flash on the nRF52840. I was able to find the write/erase time on the specs document but was not able to find anything about the reading speed (I apologize in advanced if I missed it in the document).

Thank you.

[Hung Bui]

Hi Jay,

I don't have a value, but reading from flash, directly using the address, should be very short, could be a few instruction (few clock cycles needed), just to clock the data from flash to CPU's register and then to RAM via AHB bus. I don't think the NVMC module involved here. Only when you do write or erase then the NVMC module needed. Other than that it's just direct access from CPU to AHB.

I would suggest to toggle a pin when you do a read from flash (access the flash word directly with its address) and toggle it again after you finish, and use a logic analyzer to check the pulse.

[superpak]

Were you able to get any read times? If so, can you please share? Thanks!