[time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd
David J Taylor
david-taylor at blueyonder.co.uk
Sat Nov 12 04:53:20 EST 2016
Thanks, this had me look closer at the outputs and not all RS232 chip
breakout boards shift all signals, it seems to be 4-6 lines at most.
I've seen some MAX3232 (RS232 to TTL) converters, but the better ones only
shift Rx, Tx, CTS, RTS, VCC and GND.
If I read what was suggested here earlier correctly, I need DCD for the PPS
signal and Rx, Tx for NMEA.
I plan to use this with pfsense/gpsd which lets you choose between rising
and falling edge for PPS signal processing.
I'll go ahead and order https://www.sparkfun.com/products/11189 as it
appears to do all RS232 signals and can handle voltages > 5V.
Thank you all again!
On a couple of PCs I've installed recently, RS232 add-in boards respond to
the 3.3V DCD signal, although not to 3.3V data lines. This from a ublox 6M
on a Chinese add-in board. Whilst this would obviously be unsuitable for a
stand-alone system, if you only need the PPS precision and have a suitable
source of coarse second, it may be good enough. It's working for me on a
Windows-10 PC using the loopback_ppsapi-provider.dll.
SatSignal Software - Quality software written to your requirements
Email: david-taylor at blueyonder.co.uk
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