A Simple Invert Switch
So far everything we’ve done in OpenTX has been a little more difficult than it would have been
on a conventional menu-driven transmitter. You’re probably wondering why anyone bothered to
write transmitter firmware that makes things more difficult. It’s not quite like that – Open TX does
make simple things a little more difficult, but it can make complicated things a lot simpler. Here’s
an example.
When a wheeled robot is inverted the steering remains correct, but the throttle
direction is reversed. Assigning a switch to reverse the response of the Elevator stick
axis in a conventional transmitter is complex, but in OpenTX it’s simple. On the
INPUTS
screen:
Use the scroll wheel to highlight the
Ele
line, then long-press the
ENTER
button to bring up an action menu.
Tap
ENTER
to enter the
Edit
screen.
Scroll down to
Switch
, tap
ENTER
, flip switch
SF
down then back up.
Tap enter, tap
EXIT
twice.
Long-press the
ENTER
button again.
Scroll to
Insert After
and tap
ENTER
.
Scroll down to
Weight
, tap
ENTER
, scroll the value down to
-100
.
Tap enter, tap
EXIT
twice.
How does this work?
If there are multiple lines entered under a single input, the
transmitter evaluates the first line to see if any conditions it includes are met. If they
are, that line is used. If not, it skips down a line and repeats the evaluation process.
Our first Aileron line has the condition
SA
⇑
that requires that switch
SA
be
in the
up
position – the position the transmitter expects at start-up. If switch
SA
is up the line will be accepted and the steering rate will be a controllable
50
.
If switch
SA
is not
up
, the transmitter will skip down to the second line to
evaluate its condintion. Ths second line has no condition set, so it will be
accepted and the steering rate will be a very quick
100
.
You can choose different values for the Weight to suit your driving preference --
and you can choose a different switch. Yes, you can add more lines for additional
conditions, but leave the last line with no conditions.