PCB Bring-Up & Debug — question 8 of 10
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Assume a standard external crystal circuit with two load capacitors, and a bench scope with only a passive 10x probe available initially.
You've powered a new board and confirmed every rail is within spec. But when you probe the crystal oscillator pins on the MCU with your standard 10x scope probe, you see no oscillation at all -- just a flat DC level. Walk me through how you'd isolate the cause among the probe itself, the crystal, the load capacitors, and the MCU's internal oscillator driver.