[time-nuts] PICPET- was Affordable (cheap) COTS (etc)

[Tom Van Baak]

> Has anyone else looked at the Parallax Propeller processor for timing
> functions?

Hi Brian,

Oh yes. Really nice chip. But for precise timing applications I had huge problems with phase and temperature stability of its internal PLL. I tried half a dozen different boards purchased over several years. Tech support was not interested in someone who worried about nanoseconds.

The architecture is really interesting, but it is such an odd chip, with almost zero market visibility these days, that I set aside the goal of using it as the basis of a general purpose 8-channel 6 ns precision counter. You can find various timer and counter examples at obex.parallax.com. If you make progress on the project, please let me know, ok?

By contrast, the PIC chips I use are fully synchronous so when you use 10 MHz atomic references the clock/output jitter and phase stability is almost below what I can measure here. Maybe under 2 ps. So that's why I use PIC's as the basis of all my picDIV and picPET projects. But I'm open to using something different in the future.

/tvb