mikeshellim's blog View Details
Posted by mikeshellim | Mar 13, 2017 @ 04:24 AM | 2,368 Views
GVARs are a precious resource

Gvars are the great unsung heroes of OpenTx. They're perfect for storing configuration parameters, and the Gvars menu provides a nice user-friendly front end.

However, gvars are a limited resource - only nine are available. If you run out of gvars, you'll find yourself having to delve into the Mixers menu to configure your model. So anything which saves on unnecessary use of gvars is to be welcomed. Which is where Diff comes in...

In order to implement aileron or flap differential, the standard method is to specify a gvar in the Diff field:

CH01 (RtAil)   aileron servo channel 
    [I3]Ail Weight(+100%) NoTrim Diff(GV8) [Aileron]
In the above case, a gvar makes sense, as it allows diff to be adjusted easily in the GVARS menu. But consider the following code, which allows diff to be adjusted using the rudder trim:

CH01 (RtAil)   aileron servo channel 
    [I3]Ail Weight(+100%) NoTrim Diff(GV8) [Aileron]  GV8 is set via SF3
CH15 (Diff)
    TrmR Weight(+100%) NoTrim Curve(3) [DifAdj]  TrmR sets diff value
    Adjust GV8 <= CH15  binds GV8 to CH15
Note that SF3 updates GV8 automatically with the value of the rudder trim. There is no need to set GV8 manually, yet it still takes up a precious line in the Gvars menu. Repeat this for flap diff and you have two wasted gvars.

Using mixes to calculate downward travel of ailerons and flaps

Because of this, I decided to explore an alternative method of implementing diff....Continue Reading
Posted by mikeshellim | Apr 02, 2016 @ 04:01 AM | 2,746 Views
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