4.3.1 Crystal

The SAM L22 Xplained Pro kit contains a 32.768kHz crystal that can be used as clock source for the SAM L22 device. The crystal has a cut-strap next to it that can be used to measure the oscillator safety factor. This is done by cutting the strap and adding a resistor across the strap. More information about oscillator allowance and safety factor can be found in the AVR4100 application note from Atmel.