OpenCPN

Simple histogram instrument

Simple gauge instrument

A resctangular instrument displaying a single numerical value history. Allows to select formatting and unit conversion from the SI units used by Signal K to usual units used in navigation as well as the length of the history shown by the instrument.

Table 2. Configuration parameters
Parameter Description Example

Name

Name of the instrument

Time from primary GPS

Title

Title of the instrument to be displayed

GPS Time

Timeout

Timeout in seconds. If the set numeber of seconds passes since the last update for the Signal K key displayed by the instrument pass without receiving an update, the value is considerd timed out and is replaced by dashes.

3

SK key

Fully qualified Signal K path to the value displayed by the instrument

vessels.urn:mrn:signalk:uuid:76bb2350-c92e-4e47-b3c3-e12273f21155.environment.depth.belowTransducer

Format

Format of the displayed number.

Supported formats

  • 9.9

  • 9.99

  • 9.999

  • 9

  • 009

  • 009.9

  • 09.9

  • 09.99

  • 009.99 If displaying a sign in front of the number for negative values is undesirable, select the format marked by ABS, eg. ABS(009).

Transformation

Function to be used to convert the value from the SI unit used by Signal K to human readable form

Supported transformation functions

  • None

  • RAD→DEG

  • m/s → kn

  • m/s → km/h

  • m/s → mph

  • m → feet

  • m → fathoms

  • m → NMi

  • Kelvin → Celsius

  • Kelvin → Fahrenheit

  • ratio → percent

  • Pa → hPa

  • Pa → kPa

  • Pa → MPa

  • Pa → atm

  • Pa → mmHg

  • Pa → psi

  • Hz → RPM

  • RAD/s → Degrees/min

Order

Order of values in the graph

Table 1. Value order

Lowest to highest

Lowest values drawn on top. Suitable for depth.

Highest to lowest

Highest values drawn on top. Suitable for speed etc.

History

Length of the history shown by the instrument. Selectable between 1 minute and 3 days.

  • The data for the last 1 minute are internally stored with resolution of 1 second.

  • The data for the last 1 hour are internally stored with resolution of 10 seconds

  • Older data are stored with resolution of 5 minutes

The data with different resolution are seamlessly combined together for longer time ranges.

5 minutes

Instrument width

Width of the instrument on screen

200

Instrument height

Height of the instrument on screen

200

Title color

Color of the instrument title in upper right corner

Graph color

Color of the graph line and Y-axis labels

Mean color

Color of the dynamically calculated mean value line and label

Time color

Color of the bottom labels for time

Border color

Color of the border of the instrument