Not Really, but Kind of Real Time Linux

on YouTube ↗52m

" summary

Investigation tests Raspberry Pi 3 (vanilla Linux, kernel 4.x) and BeagleBone Black PRU hardware using a logic analyzer and oscilloscope to generate a pulse 11 ms ±250 µs goal. On Raspberry Pi, tuned user‑space (SCHED_FIFO, reserved CPU core, mlock) meets the ±250 µs requirement with worst occasional spikes; busy‑wait in kernel tightens averages to a few microseconds but raises CPU/thermal concerns. BeagleBone PRU (200 MHz) delivers stability at tens of nanoseconds, essentially deterministic for pulse widths down to microseconds.

AI-written summary · about

" chapters (6)

1. 0:00Introduction and context
2. 2:48Defining real-time constraints
3. 4:11Raspberry Pi investigation
4. 35:08BeagleBone Black and PRU
5. 48:05Performance results
6. 50:05Conclusion and takeaways

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