ZERK(1) GPSD Documentation ZERK(1)

zerk - All purpose GREIS fitting

zerk [OPTIONS] [server[:port[:device]]]

zerk -h

zerk -V

zerk is an all purpose GREIS (GNSS Receiver External Interface Specification) fitting. If you do not have a Javad GPS that speaks the GREIS protocol then you can stop reading now.

This tool operates with your Javad GPS at a very low level. To understand zerk you must first be familiar with your Javad GPS and the documentation for the GREIS protocol. GREIS Guide https://www.javad.com/downloads/javadgnss/manuals/GREIS/GREIS_Reference_Guide.pdf.

zerk can decode common GREIS messages, poll the GPS status, enable and disable GPS features, and send user-generated commands to the GPS. It can read GREIS messages from a file. It can read and write directly through a serial device, or through a running gpsd instance.

zerk does not require root privileges, except maybe to access the serial port in direct mode. It will run fine as root. Running under sudo will cause loss of functionality.

The program accepts the following options:

-?, -h

Makes zerk print a usage message and exit.

-c COMMAND

Send a text string to the GPS. Accepts one parameter, COMMAND, the command string to send to the GPS. The string is sent verbatim, except a newline is appended.

-d OPTION

Disable an option in the GPS. Accepts one parameter, OPTION, the option to disable. zerk will exit after the GPS acknowledges the command, unless the -W is given.

4HZ

Disable basic GREIS messages at 4Hz. The messages are: [RT], [UO], [GT], [PV], [SG], [DP], [SI], [EL], [AZ], [EC], [SS], and [ET]

COMPASS

Disable use of the COMPASS (BeiDou) constellation.

CONS

Disable use of all constellations.

DEFMSG

Disable the default message set (/dev/msg) at 1Hz.

GALILEO

Disable use of the GALILEO constellation.

GLONASS

Disable use of the GLONASS constellation.

GPS

Disable use of the GPS constellation.

IPR

Disable all Integer Pseudo Range messages. These are [rx], [rc], [r1], [r2], [r3], [r5], [rl].

IRNSS

Disable use of the IRNSS constellation.

NMEA

Disable basic NMEA 4.1e messages at 4Hz. The messages are GBS, GGA, GSA, GST, GSV, RMC, VTG, and ZDA.

QZSS

Disable use of the QZSS constellation.

SBAS

Disable use of the SBAS constellation.

SNR

Disable all SNR messages, except [EC]. The messages disabled are: [E1], [E2], [E3], [E5], [El].

-e OPTION

Enable an option in the GPS. Accepts one parameter, OPTION, the option to enable. zerk will exit after the GPS acknowledges the command, unless the -W is given. -e accepts the same OPTIONs as -d, except the action is to enable the option.

-f FILE

Connect to a file or device. Accepts one parameter, FILE, the file or device to open. Files are opened read-only. Character devices are opened read/write, unless the -r parameter is given. Requires the pyserial module.

-O OAF

Load an Option Authorization File (OAF) into the GPS. Accepts one parameter, OAF, command file to read. The OAF is just a special case of a '.jpo' (GREIS command file). -O will send any valid .jpo file to the GPS.

-p PRESET

Send a preset command the GPS. Accepts one parameter, PRESET, the name of the command to send. zerk will exit after the GPS acknowledges the command, unless the -W is given.

COLDBOOT

Coldboot the GPS.

CONS

Poll the enabled constellations.

DM

Disable all periodic GREIS messages.

ID

Poll the receiver ID.

IPR

Poll all Integer Pseudo Range messages. These are [rx], [rc], [r1], [r2], [r3], [r5], [rl].

OAF

Poll all OAF options.

RESET

Reset (reboot) the GPS.

SERIAL

Poll receiver serial number.

SNR

Poll all Signal to Noise Ratio (SNR) messages. [EC], [E1], [E2], [E3], [E5], [El].

VENDOR

Poll GPS vendor.

VER

Poll GPS version.

-r

Read only. Do not send anything to the GPS.

-R RAW

Save all raw data from the GPS into the file RAW.

-S SPEED

Configure the GPS serial speed to SPEED bps.

-s SPEED

Set local serial port speed to SPEED bps. Default 115,200 bps.

-V

Print zerk version and exit.

-v VERBOSITY

Set verbosity level to VERBOSITY. Verbosity can be from 0 (very quiet), to 4 (very noisy). Default 2.

-W

Force waiting the entire wait time. No early exit for completion of -d, -e or -p command.

-w WAIT

Wait for WAIT seconds before exiting. Will exit early on command completion of -d, -e or -p command, unless -W is given. Default 2.0 second.

By default, clients collect data from the local gpsd daemon running on localhost, using the default GPSD port 2947. The optional argument to any client may override this behavior: [server[:port[:device]]]

For further explanation, and examples, see the ARGUMENTS section in the gps(1) man page

Options can be placed in the ZERKOPTS environment variable. ZERKOPTS is processed before the CLI options.

Print current Javad serial port of GPS connected to local running gpsd:

 zerk -c "print,/cur/term"

Decode raw log file:

zerk -r -f greis-binary.log -v 2

Change GPS port speed of device on /dev/ttyAMA0 to 230,400 bps:

zerk -S 230400 -f /dev/ttyAMA0

Watch entire GPS reset cycle:

zerk -p RESET -v 2 -w 20 -W

Poll SVs Status:

zerk -W -w 2 -v 2 -c "out,,jps/{CS,ES,GS,Is,WS,QS}"

Dump gpsd data from remote server:

zerk -v 2 -w 5 server

0

on success.

1

on failure

zerk is written to conform to the official Javad documentation for the GREIS protocol. GREIS Guide https://www.javad.com/downloads/javadgnss/manuals/GREIS/GREIS_Reference_Guide.pdf.

gpsd(8)

Project web site: https://gpsd.io/

This file is Copyright 2013 by the GPSD project
SPDX-License-Identifier: BSD-2-clause

Gary E. Miller

2023-01-10 GPSD, Version 3.25