GPS Module

HW-595 Board

uBlox GPS Board

• Based on uVBlox 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

• 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

• U-Center

GPSD

• 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 via, or xgps

PPS

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

Check PPS signal:

ppstest /dev/pps0
ppscheck /dev/ttyUSB0