"Pierce oscillator is a derivative of the Colpitts oscillator."

....... осцилатора в контролер на Моторола може да се включва и по двете топологии, коя точно се определя от друг пин.

...
Подсъзнателно залагам на колпица, но когато си признаеш за какво мцу става дума колегите може да имат опит.

In the Colpitts configuration stray reactances tend to appear across the crystal. This degrades performance
and reliability, and the effect is worsened by biasing elements in this configuration. In the Pierce
configuration, performance and reliability are considerably less affected because stray elements tend to
appear across the load capacitors (i.e., stray capacitance tends to add to the load capacitors, so it’s easy to
compensate by simply reducing the load capacitors' value).
Freescale’s Colpitts configuration provides an amplitude limitation control (ALC) loop which permits
lower current consumption and lower levels of RF emissions. However, the Pierce configuration is less
susceptible to noise, doesn't have a DC voltage across the crystal, and starts up faster.
Unless the lower current consumption of the Colpitts configuration is required, it is highly recommended
to opt for the Pierce configuration due to its better reliability.