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The stm32 datasheet says that the number of wait states for reading the FLASH memory have to be configured based on the voltage used to power the microcontroller, and frequency. When running at 120MHz, assuming the voltage is higher than 2.7V I configured it with three wait states but the microcontroller crashes under high CPU load.

I see (based on https://github.com/underverk/SmartWatch_Toolchain/blob/master/src/driver_power.c) that there's a power management unit which probably powers the microcontroller, although Sony's site doesn't even acknowledge its existence. What is the voltage used to power the microcontroller?

AstroCB
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user2671945
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  • You could find it out by trial-and-error, or you could ask in a more appropriate site like [Super User](http://www.superuser.com). – Geeky Guy Aug 23 '13 at 18:06
  • Actually Sony said to hardware hackers to post questions here on stack overflow http://developer.sonymobile.com/services/open-smartwatch-project/developer-questions/ Also, finding by trial and error is NOT a reliable solution, due to manufacturing tolerances. I can find the wait states that work for my watch, but if I'm pushing for performance will my settings work when my firmware is used on another watch? The only reliable information we have is from ST, but that information depends on the voltage (which is unknown unless I open up and destroy my watch) – user2671945 Aug 23 '13 at 18:08
  • [I've pinged the person you likely want to reach](http://stackoverflow.com/questions/18379826/smartwatch-extension/18388247#comment27041521_18388247), to clear up the problem with that page. – Michael Petrotta Aug 23 '13 at 18:17
  • I hope this doesn't end up with no place where to ask hardware related questions. Given that hardware schematics aren't available (http://stackoverflow.com/questions/17088504/smartwatch-h-w-schematic), this would cut the only communication channel with those who have an idea about how the hardware works. – user2671945 Aug 23 '13 at 20:41

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The micro controller is fed with 1.8V. When in dfu-mode, it is changed to 3.3V.

Jerker
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