Widgets Engine Gauges

Engine & Data Gauges

The four general-purpose gauges that show any FIX value against its range and limits. How they read, the EGT leaning modes and the cylinder groups are on Engine Monitoring; this page is the full option list. Each table is generated from pyEFIS's instrument registry; see Widget Reference.

type:	Shape	Units shown by default
arc_gauge	An arc with a pointer and a readout.	no
horizontal_bar_gauge	A horizontal bar and a readout.	yes
vertical_bar_gauge	A vertical bar and a readout; the cylinder bars.	yes
numeric_display	A readout only, coloured by the limits.	no

All four:

• have no FIX key of their own: set dbkey;
• take their range from the FIX item's minimum and maximum, and their bands from its lowAlarm, lowWarn, highWarn and highAlarm, set in fix-gateway through the aircraft parameters;
• can be selected with the knob to set their value (below).

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arc_gauge

Arc Gauge · palette category gauge

How it reads and flies: Engine Monitoring.

Option	Configurator label	Default	Values	What it does
dbkey	FIX key	empty	FIX key	FIX-database key whose value this gauge displays
name	Name	empty		label drawn on the gauge (e.g. OIL P, CHT)
decimal_places	Decimal places	1		digits after the decimal point in the readout
show_units	Show units	off	on / off	append the FIX key's engineering units to the readout
segments	Segments	0		0 = solid band; >0 draws a segmented (LED-style) band
name_location	Name location	top	top, right	where the name label sits relative to the gauge

Values it reads from the FIX item, set in fix-gateway (the aircraft parameters), not on the panel:

Value	From	Meaning
Min	min	Range minimum
Max	max	Range maximum
lowAlarm	aux	Low alarm (red)
lowWarn	aux	Low warning (yellow)
highWarn	aux	High warning (yellow)
highAlarm	aux	High alarm (red)

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vertical_bar_gauge

Vertical Bar Gauge · palette category gauge

How it reads and flies: Engine Monitoring.

Option	Configurator label	Default	Values	What it does
dbkey	FIX key	empty	FIX key	FIX-database key whose value this gauge displays
name	Name	empty		label drawn on the gauge (e.g. OIL P, CHT)
decimal_places	Decimal places	1		digits after the decimal point in the readout
show_units	Show units	on	on / off	append the FIX key's engineering units to the readout
segments	Segments	0		0 = solid bar; >0 draws a segmented (LED-style) bar

Values it reads from the FIX item, set in fix-gateway (the aircraft parameters), not on the panel:

Value	From	Meaning
Min	min	Range minimum
Max	max	Range maximum
lowAlarm	aux	Low alarm (red)
lowWarn	aux	Low warning (yellow)
highWarn	aux	High warning (yellow)
highAlarm	aux	High alarm (red)

Only the vertical bar has the EGT modes and the hottest-cylinder ball. Set them in YAML:

Option	Default	What it does
egt_mode_switching	off	Respond to the Set EGT mode actions.
normalize_range	unset	The span the bar covers in Normalize.
highlight_key	unset	A FIX key such as EGTMAX1; a ball is drawn while this bar's value equals it.

See Engine Monitoring.

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horizontal_bar_gauge

Horizontal Bar Gauge · palette category gauge

How it reads and flies: Engine Monitoring.

Option	Configurator label	Default	Values	What it does
dbkey	FIX key	empty	FIX key	FIX-database key whose value this gauge displays
name	Name	empty		label drawn on the gauge (e.g. OIL P, CHT)
decimal_places	Decimal places	1		digits after the decimal point in the readout
show_units	Show units	on	on / off	append the FIX key's engineering units to the readout
segments	Segments	0		0 = solid bar; >0 draws a segmented (LED-style) bar

Values it reads from the FIX item, set in fix-gateway (the aircraft parameters), not on the panel:

Value	From	Meaning
Min	min	Range minimum
Max	max	Range maximum
lowAlarm	aux	Low alarm (red)
lowWarn	aux	Low warning (yellow)
highWarn	aux	High warning (yellow)
highAlarm	aux	High alarm (red)

A limit of exactly 0 is not drawn on a horizontal bar.

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numeric_display

Numeric Display · palette category text

How it reads and flies: Engine Monitoring.

Option	Configurator label	Default	Values	What it does
dbkey	FIX key	empty	FIX key	FIX-database key whose value is displayed
decimal_places	Decimal places	1		digits after the decimal point in the readout
font_mask	Font mask	000		widest string the readout reserves space for (sizing)
show_units	Show units	off	on / off	append the FIX key's engineering units to the readout

Values it reads from the FIX item, set in fix-gateway (the aircraft parameters), not on the panel:

Value	From	Meaning
Min	min	Range minimum
Max	max	Range maximum
lowAlarm	aux	Low alarm (red)
lowWarn	aux	Low warning (yellow)
highWarn	aux	High warning (yellow)
highAlarm	aux	High alarm (red)

It colours the value by the limits like the others, without a band. When it is selected for editing it shows the cyan ring and knob icon from The Panel at a Glance; the bar and arc gauges turn orange instead.

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Options every gauge takes in YAML

These are read by all four but are not in the configurator's list. Except for the unit switches, pyEFIS applies them and logs that they are undeclared.

Option	Default	What it does
temperature: true, pressure: true	off	Let the Units button switch this gauge between °C and °F, or inHg and hPa.
altitude: true	off	The same for ft and m, on numeric_display only.
clipping	off	Hold the value, and any edit, inside the item's range.
encoder_set_key	the dbkey	The FIX key the knob edits.
encoder_multiplier	1	Inner-knob step.
encoder_coarse_multiplier	10	Outer ring step, as a multiple of the inner.
encoder_set_real_time	off	Write each step at once, rather than on the push.
touch_edit	off	Select it by touch as well as with the knob.
encoder_order	unset	Its place in the knob's order.

Selected and turned, a gauge changes its value; a push keeps it; leaving it until the knob times out puts the old value back.

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Ganged gauges

Prefix a gauge type with ganged_ to repeat it across groups: this is how the stock screens build their cylinder rows. gang_type is required. common_options apply to every member of a group, and a member's own options: override them.

- type: ganged_vertical_bar_gauge
  gang_type: horizontal       # required: horizontal or vertical
  row: 8
  column: 1
  span: {rows: 5, columns: 27}
  groups:
    - name: EGT
      common_options:
        egt_mode_switching: true
        normalize_range: 400
      instruments:
        - {options: {name: "1", dbkey: EGT11, show_units: false}}
        - {options: {name: "2", dbkey: EGT12, show_units: false}}
        - {options: {name: "3", dbkey: EGT13, show_units: false}}
        - {options: {name: "4", dbkey: EGT14, show_units: false}}

In the configurator, use the palette's cylinder groups instead. The rules for groups, gaps and disabled are on Customizing Beyond the Configurator.