External flash available

TinyCLR OS
1

What is the quantity of external Flash really accessible to users ?

The doc says that there are 8MB for deployment (if needed) and 8MB reserved for future use. So that would mean that it remains nothing for custom use.
But at the same time, the QSPI example is using a 16MB size, with no restriction a priori.

I don’t really understand how that external Flash is used/shared :frowning:

2

The docs need to be updated. You get 8 for deployment and 8 for you to store whatever you want. We will update docs the week.

3

Ok, thank you, Gus.
Then other questions :wink:

  • What if I don’t want to use the extra 8MB for deployment : can I consider the whole 16MB available for custom use ? (like your example for QSPI)

  • On the contrary, if I use the 8MB for deployment, what is the start address of the remaining 8MB : 0x00000000 or 0x08000000 ?

  • Is there a software way to detect if the 8MB are assigned to deployment ?

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4

All very good questions. Let me double check and get beck to you.

5
  1. Depend how you config your sector size, capacity wheb config TFS. Answer is Yes, you can use 16MB.
  2. The address start at 0x00000000.
  3. There is a flag to know external flash enable. If it is enable, mean 8MB left. IsEnabledExtendFlash I beleive.
6

@Dat_Tran : thank you !

Are you really sure about your answer to point #2 ? I would have thought that TinyCLR would have eaten the first 8MB for its own use (deployment area in this case) before leaving the following 8MB at 0x08000000 for custom use.

7

I probably understand your question incorrectly, but when use storage to read write qspi, the address in API always start from 0x00000000.

We put deployment in last 8MB but this is not a reason to start 0x00000000

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8

You have understood correctly :slight_smile:

Now I will have to get back to the QspiMemory driver to include some sanity checks when/if external flash is used for deployment.
I have all the needed infos now, thank you !

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