GPS Module: Difference between revisions

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* UART: 9600 bps 8N1, TTL levels buffered by 220R resistors
* UART: 9600 bps 8N1, TTL levels buffered by 220R resistors
* [https://en.wikipedia.org/wiki/Hirose_U.FL U.FL] connector supplies 3.3 V to active antenna
* [https://en.wikipedia.org/wiki/Hirose_U.FL U.FL] connector supplies 3.3 V to active antenna
* Crystal Osc, not TCXO


* Data in [http://www.gpsinformation.org/dale/nmea.htm NMEA] 0183 format
* Data in [http://www.gpsinformation.org/dale/nmea.htm NMEA] 0183 format

Revision as of 07:26, 27 February 2023

HW-595 Board

uBlox GPS Board
  • Based on uBlox NEO-6M-0-001
  • 5V operation (3.3 V regulator onboard)
  • UART: 9600 bps 8N1, TTL levels buffered by 220R resistors
  • U.FL connector supplies 3.3 V to active antenna
  • Crystal Osc, not TCXO
  • Data in NMEA 0183 format
  • More background here

Board pinouts:

Pin Function Description
1 PPS 1 pulse/s, synchronised at rising edge, length 100 ms
2 RXD UART input
3 TXD UART output
4 GND Ground
5 VCC 3.3 - 5 V

PPS can be reconfigured as a frequency reference:

  • Send PPS to UART via CTS
  • 0.25 Hz - 10 MHz
  • Configure in u-Center here
  • Output has high frequency accuracy, but suffers from jitter except at a few specific frequencies

Software

U-Center

GPSD

Enable and start gpsd. Should auto-detect which UART is GPS connected to, etc:

systemctl enable gpsd
systemctl start gpsd

Use gpsmon to monitor GPS data, or xgps

Pulse Per Second (PPS)

dnf install pps-tools
modprobe pps_ldisc
ldattach 18 /dev/ttyS0

Check PPS signal:

ppstest /dev/pps0
ppscheck /dev/ttyUSB0