Re: [gpsd-dev] PPS not showing in gpsmon/gpsd on RPi 3

[Frank Nicholas]

On Apr 23, 2016, at 8:15 AM, Oliver Jowett <address@hidden> wrote:

On 23 April 2016 at 11:28, Eric S. Raymond <address@hidden> wrote:

gpsd:WARN: KPPS:/dev/pps0 kernel PPS unavailable, PPS accuracy will suffer
gpsd:WARN: PPS:/dev/pps0 die: no TIOMCIWAIT, nor RFC2783 CANWAIT

This looks similar to something I saw a while back where the serial driver (a usb-serial driver in my case) did not implement asynchronous notifications of handshake line state changes. So neither kernel PPS nor TIOMCIWAIT worked. (I never did get PPS working in that case)

What's the underlying driver for ttyAMA0 on the Pi 3?

Oliver

You have to remember that ttyAMA0 ONLY has Tx & Rx.  The pin used for PPS is a general purpose GPIO pin - not a serial port control pin.  So the driver for ttyAMA0 is not involved for PPS.