Does Zigbee persistent data need 48kB or 48 pages of flash?

RE: Does Zigbee persistent data need 48kB or 48 pages of flash?

Øyvind — Tue, 29 Jan 2019 07:27:05 GMT

Great, thank you!

RE: Does Zigbee persistent data need 48kB or 48 pages of flash?

Edvin — Tue, 29 Jan 2019 07:21:54 GMT

Hello,

I just received an answer from our ZigBee team, and they confirm your suspicion:

From the second link, if it is correct that you need the space from 0x000F4000 to 0x00100000, which is 48kB. 48kB is 12 FDS pages. From sdk_config:

// <o> FDS_VIRTUAL_PAGE_SIZE - The size of a virtual flash page.

// <i> Expressed in number of 4-byte words.

// <i> By default, a virtual page is the same size as a physical page.

// <i> The size of a virtual page must be a multiple of the size of a physical page.

// <1024=> 1024

// <2048=> 2048

#ifndef FDS_VIRTUAL_PAGE_SIZE

#define FDS_VIRTUAL_PAGE_SIZE 1024

#endif

So the number of pages should be set to 12, which makes up 48kB, which is what the persistent storage needs.

Thank you for your input!

Best regards,

Edvin

RE: Does Zigbee persistent data need 48kB or 48 pages of flash?

Edvin — Wed, 23 Jan 2019 15:00:01 GMT

It is a good catch, and a valid question 🙂

Edvin

RE: Does Zigbee persistent data need 48kB or 48 pages of flash?

Øyvind — Wed, 23 Jan 2019 07:45:08 GMT

Thanks, no hurry. Just found it curious that so much flash should be reserved, so I thought I'd ask.

RE: Does Zigbee persistent data need 48kB or 48 pages of flash?

Edvin — Wed, 23 Jan 2019 07:34:12 GMT

Hello,

I see what you mean. I have forwarded this to our ZigBee team to see whether it actually is a bug, but I agree that it says it requires 32kB of flash from the "Typical flash and RAM requirements table" and 48kB from the "Zigbee stack flash and RAM layout". I assume this is 32kB + a config page or a swap page.

They replied that they will look into this, but that they can't guarantee to have an answer until next week. I am sorry for the delay. I will get back to you as soon as I hear from them.

However, 48kB of persistant storage (FDS pages) would suggest 0x0C = 12 pages, so if you'd like, you can try with this, and see whether you run into some unexpected issues that you can't reproduce with 0x30 = 48 reserved pages.

Best regards,

Edvin