I'm trying to find a spec for the electrical requirements for providing an external clock to the K60.
I currently have a circuit that puts a sinewave on "EXTAL", a sinewave that has a DC component of about 0.8V and a pk-to-pk voltage of about 0.7V
I get intermittent hanging at this in bsp_cm
while ((MCG_S & MCG_S_IREFST_MASK) != 0x00U) /* Check that the source of the FLL reference clock is the external reference clock. */
making me suspicious of the clock.