[GPS_Standard] Motorolsa UT+ Encore help pse

[Dave Platt]

>> Hi, Perhaps a bit off topic but I'm trying to use a motorola UT+ encore for 
>> the VE2ZAZ standard and NMEA location/time output
>> the 1pps is fine but unable to resolve NMEA

> "The UT+ Oncore is not suitable for general GPS uses,
> such as APRS, that
> require NMEA output.  The output of the UT+ Oncore is in Motorola Binary
> Format."

The Oncore Motorola-protocol-only GPS receivers are
supported by the Linux/Unix "gpsd" software... there
is a driver for this protocol.

It looks to me as if you can then use "gpspipe" to connect
to gpsd, and get output which includes an NMEA conversion
of the Oncore binary data ("gpspipe -r").

I've been using an Oncore (originally an early VP and
now a UT+) in my VE2ZAZ standard for over a year, with
a dual Maxim TTL-to-RS232 converter (I forget exactly
which chip) and two serial ports on the PC.  The 1PPS
signal is buffered, and drives both the serial handshaking
line (for the PC's carrier-detect input) and the VE2ZAZ
controller.  "gpsd" receives the Motorola binary protocol
and monitors the CD line on one serial port, and feeds time
information to "ntpd" via the SHM shared-memory driver.

Works quite well in practice.  The timing precision isn't
quite as good as if I used the Linux kernel's serial-port
"PPS" timing discipline code (which does the carrier-detect
sampling down in the kernel's interrupt layer) but that PPS
driver isn't yet in the Debian kernel version I'm using,
and I might need an extra serial port to implement it.