Accessing SRAM from bit controller

Much like this topic I am trying to access the SRAM of a microbit on startup, below,

I tried to use the code given in the topic above but I cannot understand nor can get it to work.

The SRAM of the microbit is given in the memory address of 0x20000000, on page 21 of the datasheet.

I only want the bits outputted to the serial monitor so I can then analyse it, I’m sure its not too difficult, but I’m not too sure where to start.

The link you provided is a hardware data sheet.

Using the SRAM any way you want is a software function… typically in a high-level language like C/C++, you don’t need to manipulate specific locations in memory - you can, but it’s generally not a good idea for a beginner.

You could of course revert to assembly language which gives direct access to all the hardware, but requires a higher understanding of the specific device architecture.

What are you trying to do, and why - there’s probably a straightforward way to do it from C.

Ultimately, the end goal is to analyse it to maybe see if the microbit can act as a PUF, this is expanded on the topic linked.

I linked the datasheet to clarify the memory address of the SRAM.

An interesting read…

What I’d suggest might be to overclock the processor during startup, to expose any marginal timing errors in individual hardware - prior to executing code.
I doubt the range of variance would be very useful or consistent over tine & temperature, but I suspect modern semiconductor manufacturing techniques are actively trying to eliminate chip level power-up variations.

Your originally referenced thread discusses a lot of options and questionable solutions.

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