Merge pull request #2765 from davidzwa/patch-1
Update faq.adoc with memory.x definition helping hand
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				@ -208,3 +208,26 @@ Tools like `cargo size` and `cargo nm` can tell you the size of any globals or o
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=== For Max Stack Usage
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Check out link:https://github.com/Dirbaio/cargo-call-stack/[`cargo-call-stack`] for statically calculating worst-case stack usage. There are some caveats and inaccuracies possible with this, but this is a good way to get the general idea. See link:https://github.com/dirbaio/cargo-call-stack#known-limitations[the README] for more details.
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== The memory definition for my STM chip seems wrong, how do I define a `memory.x` file?
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It could happen that your project compiles, flashes but fails to run. The following situation can be true for your setup:
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The `memory.x` is generated automatically when enabling the `memory-x` feature on the `embassy-stm32` crate in the `Cargo.toml` file.
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This, in turn, uses `stm32-metapac` to generate the `memory.x` file for you. Unfortunately, more often than not this memory definition is not correct.
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You can override this by adding your own `memory.x` file. Such a file could look like this:
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```
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MEMORY
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{
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  FLASH (rx) : ORIGIN = 0x08000000, LENGTH = 1024K
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  RAM (xrw)  : ORIGIN = 0x20000000, LENGTH = 320K
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}
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_stack_start = ORIGIN(RAM) + LENGTH(RAM);
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```
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Please refer to the STM32 documentation for the specific values suitable for your board and setup. The STM32 Cube examples often contain a linker script `.ld` file. 
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Look for the `MEMORY` section and try to determine the FLASH and RAM sizes and section start.
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If you find a case where the memory.x is wrong, please report it on [this Github issue](https://github.com/embassy-rs/stm32-data/issues/301) so other users are not caught by surprise.
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