The datasheet goes on to say that "the nRESET pin is internally connected to VDD with a pull up resistor of 50 kΩ." So... why are there two options for how to configure the nReset pin when it is not being used? Why not just recommend that it should be left floating (since it is already pulled high internally)? And, if there are indeed technical reasons for when the pin should be externally pulled up to VDD (for better noise immunity, as an example) then let us know what those technical reasons are.
Note that U4, a 10 MHz MEMS oscillator, is also very close to the microcontroller’s clock input pin. It’s always a good idea to minimize the length of traces carrying high-frequency digital signals. First of all, there are noise benefits: a shorter, more direct trace reduces the amount of noise that would otherwise be coupled into adjacent traces, and a shorter trace also reduces electromagnetic interference (EMI) because it is less effective as an antenna. The second issue is related to transmission-line effects. Minimizing trace length is a simple way to avoid problems related to signal reflections. However, reflection is not a significant concern at frequencies in the 10 MHz range, unless you are dealing with long interconnections or a very large PCB.
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