1-Wire Peripherals - Triadis Engineering Glide Computer and Navigation System Owner's Manual

2.9 1-Wire peripherals

briefly once per second. When external power is restored, Altair
beeps once and the LED switches off.
When turning on Altair Pro while the external power has been
disconnected or depleted, power to external devices (e.g. Vega and
FLARM) will be disconnected. This is a design feature to draw
the pilot's attention to the external power supply, and prevent the
pilot from accidentally starting the system and take-off without the
main battery on.
The backup battery is designed to allow the pilot to make a final
glide to a safe landing field if the main battery in the glider fails. It
is not intended to be used for extended flights with all instruments
on and no external power.
The 'System Status' dialog in XCSoar shows the current external
battery supply voltage. This is accessed through the menu:
INFO Status System
A battery monitoring facility in XCSoar, providing a running en-
durance estimate, is under development.
Altair supports expansion via attaching peripheral sensors and switches
via the the Dallas Semiconductor/Maxim 1-Wire bus. These may
include user interface devices, sensors or other instruments and
switches. Example applications, other than the control stick grip
buttons already mentioned, include:
Temperature/humidity sensor
Compass
Gyroscope, attitude reference system
Fuel gauge
Engine monitoring sensors
When using the 1-Wire bus, it is important to note that Altair does
not generally supply power to the devices, rather the only electri-
cal connections between Altair and the devices are the 1-Wire bus
signal and ground lines as shown in Figure 2.1.
An optional eight port digital input node 1-Wire node is available
as an accessory. This node allows up to eight digital switch inputs
to be connected to the node and the node itself is connected to
Altair. Should the need arise, multiple nodes may be placed on the
network, allowing for almost limitless expansion.
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