devel@ntpsec.org said: > As far as I understand the sources, setting up an echo allows a PPS client > to register a callback function with the PPS device to be called when a PPS > event happens. The default echo function simply outputs "echo: assert" or > "echo: clear". I guess one could indeed toggle a GPIO from a suitably > defined PPS client.
Thanks. It may be easier to experiment with a real serial port since it would be easy to pick one of the output modem control signals. With gpio we could make the dtoverlay line take 2 pin numbers. It shouldn't be a big deal, but it's another complication. As a hack, we could just use the next pin number. I think the hardware is safe if you pick a wrong pin number. If the dtb isn't setup right, the gpio bit isn't connected to the output pin. The other hack we would need to to is patch the code in ntpd that sets up the PPS stuff not to turn off the edge it doesn't need so the output pin can get reset to be ready for the next time. -- These are my opinions. I hate spam. _______________________________________________ devel mailing list devel@ntpsec.org http://lists.ntpsec.org/mailman/listinfo/devel