nRF52: Write/erase flash cycles confusion

[ThierryQ]

Hi,

I have a small question regarding flash write/erase cycles and I was unable to find a clear answer.

I can see in NRF52 specs:

• Flash write/erase cycles: 10 000.
• Amount of writes allowed in a block between erase: 181

I would like to know if 10000 is related to write + erase or only erase.

I means, if I have below scenario:

• erase page1
• write page1 (10bytes)
• write page1 (+10bytes)

How many flash cycle I will consume ? 1 or 3 ?

Thank you,

Thierry.

[sidekick]

Without looking at the spec, my quick reply is that in general, you need to consider the erase limit. So in your case, it is 1. Note that, you might still get correct result (a read from an address returns the most recent write on that address) even after exhausting the erase limit, however the flash vendors do not guarantee that. Also, I don't think the limit would be 10000, that's quite low endurance, it should be around 100000 or more.

[ThierryQ]

Thank you for your quick reply.

Someone else can confirm: write action will not impact the flash cycle (Only erase will do that) ?

I need to be very careful regarding this information, my product will fully dependends to it. I need to write during 3 years on this flash and the frequency of it will be directly determined by this information.

Thierry