Another milestone down. My PCA9685-based PWM driver is now outputting a clean 250 Hz signal — and here it is on the scope:

This trace, captured on a Tektronix TDS 210, confirms that my PWM output is steady and accurate at 250 Hz with ~70% duty cycle. Each division is 500 µs, so we’re looking at a 4 ms period — and the high pulse lasts just under 3 ms, right on target.
⚙️ System Details:
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Host: Raspberry Pi 4
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PWM Driver: PCA9685 @ 0x40 (I²C)
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PWM Output: 250 Hz, 70% duty
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Scope: Tektronix TDS 210
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Probe: 10x (CH2: 50 mV/div)
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Coupling: DC
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Trigger: Channel 2, rising edge
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Bandwidth Limit: 20 MHz
This signal will ultimately drive an analog output stage via low-pass filtering — a lightweight DAC solution for the SigCore UC platform. Scope confirms it's rock-solid. Next step: verify analog voltage after filtering.
Edward
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