2020-12-17 06:25 AM
The schematics on page 5 says regarding HSE external"
"C31 must be placed in order
to avoid stubs on XTA path
when C31 not fitted."
Probably R41 is meant to be placed.
2020-12-17 09:47 AM
The stubs on XTA path are avoided leaving unpopulated the following components: R39, or R40, or even C31.
When using the TCXO, R39 and R40 must be removed to avoid stubs.
When using XO, R41 and C31 must be removed to avoid stubs.
And, in fact, R41 is never fitted, just placed in case of.