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Taranis: A Volume Control That Doesn't Take Up Any Pots or Switches
for OpenTX version 2.1.9
Like my other scripts so far, volume.lua is implemented like a telemetry script but doesn't actually provide telemetry. (But in this case it could with modification.) What it does is provide a way to adjust volume and store the setting without using any of the switches, knobs, or sliders that are otherwise used to control your model. Instead, the buttons next to the display are used.
The script needs one global variable ("GV"), which you can name "Volume." It can be any one of the nine global variables in each of your model memories and can even be a different GV for each model, although that would require multiple copies of volume.lua with minor changes to each copy and different filenames. I'm using GV1 in my radio and in the examples that follow.
There are installation instructions embedded in the script but I'll post more detailed instructions here.
for OpenTX version 2.1.9
Like my other scripts so far, volume.lua is implemented like a telemetry script but doesn't actually provide telemetry. (But in this case it could with modification.) What it does is provide a way to adjust volume and store the setting without using any of the switches, knobs, or sliders that are otherwise used to control your model. Instead, the buttons next to the display are used.
The script needs one global variable ("GV"), which you can name "Volume." It can be any one of the nine global variables in each of your model memories and can even be a different GV for each model, although that would require multiple copies of volume.lua with minor changes to each copy and different filenames. I'm using GV1 in my radio and in the examples that follow.
There are installation instructions embedded in the script but I'll post more detailed instructions here.
- Download volume.txt from the link below, edit it as needed, rename it to volume.lua, and store it in SCRIPTS/TELEMETRY on your SD card. A follow-up post will display the script so that you can copy and paste it into a text editor if you wish.
- The GV that you use for volume control needs to be set to "Flight mode 0 value" in flight modes FM1 through FM8.
- On the Inputs page, create an input to read the volume global variable. In this example I use [I7]:
Code:[I7]Vol MAX Weight(GV1)
gimbtest.lua is designed to run as a telemetry screen, although it doesn't actually provide telemetry. It checks each of the four stick functions, throttle, aileron, elevator, and rudder, for the 2049 possible stick values recognized by OpenTX, which range from -1024 to +1024. When each stick value is detected the corresponding screen pixel is set, and slow, careful movement of the sticks will eventually produce a display of which positions are detectable and which are not.
Pressing MINUS (-) will clear the screen and restart the test, and long-pressing EXIT will exit the screen.
When gimbtest.lua is run in Companion simulator the result is not impressive because the values obtained from mouse movement by Companion are very coarse compared to the values obtained from the Taranis gimbals:
The vertical lines in the display each consist of four line segments, one for Thr, one for Ail, one for Ele, and one for Rud. The left segments indicates that the value of -1024 was reached, the center segments indicates that zero was reached, and the right segments indicates that +1024 was reached. All other positions are indicated by individual pixels, with the negative values represented on the left side of center and the positive values represented on the right side.
You can see in the image above that when the script was run on Companion simulator the center segment for Thr did not appear, indicating that a zero reading from the throttle stick could not be obtained.
...Continue Reading
Pressing MINUS (-) will clear the screen and restart the test, and long-pressing EXIT will exit the screen.
When gimbtest.lua is run in Companion simulator the result is not impressive because the values obtained from mouse movement by Companion are very coarse compared to the values obtained from the Taranis gimbals:
The vertical lines in the display each consist of four line segments, one for Thr, one for Ail, one for Ele, and one for Rud. The left segments indicates that the value of -1024 was reached, the center segments indicates that zero was reached, and the right segments indicates that +1024 was reached. All other positions are indicated by individual pixels, with the negative values represented on the left side of center and the positive values represented on the right side.
You can see in the image above that when the script was run on Companion simulator the center segment for Thr did not appear, indicating that a zero reading from the throttle stick could not be obtained.
...Continue Reading
This is a continuation of What happens when an offset is applied to a stick-controlled channel, where I'll describe how to implement optimizing of offsets to prevent clipping and stopping short. It's also an example of deriving a method with algebra and then translating it into OpenTX code. For another example, I recommend Differential without GVARs, posted today by Mike Shellim.
To recap, the principle of what I'm calling Optimized Outputs is to maintain access to both Min and Max limits even when the center position is offset. It's equivalent to what happens with off-center subtrims on the Outputs page if subtrims are set to "normal", but not if they're set to "linear." The desired behavior is represented by the green line in this graph:
The red line represents an offset that's not optimized, so that if full stick travel is used with 100% weight, the result is clipping at one end and stopping short at the other end.
The blue line represents an input without any offset.
My algorithm is to compute the distance the stick is from the end of its travel and reduce the weight of the offset accordingly, so that by the time the stick has reached the end of its travel the offset has been reduced to zero and the output has arrived exactly at its limit, just as it does when no offset is applied.
For any position (P) that a stick can be in within the range of -100% to +100%, the distance from the nearest endpoint (D) equals one minus the...Continue Reading
To recap, the principle of what I'm calling Optimized Outputs is to maintain access to both Min and Max limits even when the center position is offset. It's equivalent to what happens with off-center subtrims on the Outputs page if subtrims are set to "normal", but not if they're set to "linear." The desired behavior is represented by the green line in this graph:
The red line represents an offset that's not optimized, so that if full stick travel is used with 100% weight, the result is clipping at one end and stopping short at the other end.
The blue line represents an input without any offset.
My algorithm is to compute the distance the stick is from the end of its travel and reduce the weight of the offset accordingly, so that by the time the stick has reached the end of its travel the offset has been reduced to zero and the output has arrived exactly at its limit, just as it does when no offset is applied.
For any position (P) that a stick can be in within the range of -100% to +100%, the distance from the nearest endpoint (D) equals one minus the...Continue Reading
If you program a switch to operate a motor you'll find that the way switches work seems upside-down. Using SE as an example, SE↑ = -100% and SE↓ = +100%.
The simplest way to correct that is to read the switch with a mix that has a negative weight, like this:
But here's the pitfall: Suppose you want the motor to come on slowly but turn off immediately. You would probably expect this to work:
This looks like it would take one second to slowly increase the throttle to full power when SE is switched to SE↑, but immediately turn the motor off when SE is switched to SE↓. However, it works exactly the opposite way. The mix above causes the throttle to jump to full power immediately with SE↑ but slowly decrease to off over the course of one second with SE↓.
This is what works:
The reason for this is that, contrary to data flow diagrams that were promised to be corrected over two months ago 
, the Delay and Slow functions are processed at the beginning of a mix, not at the end.
The simplest way to correct that is to read the switch with a mix that has a negative weight, like this:
Code:
CH07 (ESC) SE Weight(-100%) [Motor]
Code:
CH07 (ESC) SE Weight(-100%) Slow(u1.0:d0) [Motor]
This is what works:
Code:
CH07 (ESC) SE Weight(-100%) Slow(u0: d1.0) [Motor]
, the Delay and Slow functions are processed at the beginning of a mix, not at the end.
In a glider setup there are many cases where offsets are applied to stick-controlled channels. The flaps and ailerons are offset upward for reflex and downward for camber. The elevator is offset downward for flap compensation. The rudder is offset left or right when aileron-to-rudder mixing is applied. On top of that, when trim is added to any stick it results in an offset. What happens when an offset is applied?
The control surface moves to the desired offset position when its stick is centered, but when the stick is moved away from center and nears the limit of its travel in either direction, bad things can happen.
When the stick is moved in the same direction that the offset is applied, and the stick input plus the offset reaches or exceeds the -100% to +100% limit, no further movement of the stick in that direction will do anything. As long as you've set up your Outputs screen properly it won't result in any damage or stress, but you still have a region of stick travel that's essentially dead. That's Clipping.
When the stick is moved in the direction opposite the direction the offset is applied, and the stick reaches the limit of its travel, the output will stop short of it's limit and a portion of the output range will be unavailable no matter how you move the stick. That's Stopping Short.
The solution is to handle offsets a little differently by giving stick input priority over them. Compute the distance the stick is from the end of its travel and...Continue Reading
The control surface moves to the desired offset position when its stick is centered, but when the stick is moved away from center and nears the limit of its travel in either direction, bad things can happen.
When the stick is moved in the same direction that the offset is applied, and the stick input plus the offset reaches or exceeds the -100% to +100% limit, no further movement of the stick in that direction will do anything. As long as you've set up your Outputs screen properly it won't result in any damage or stress, but you still have a region of stick travel that's essentially dead. That's Clipping.
When the stick is moved in the direction opposite the direction the offset is applied, and the stick reaches the limit of its travel, the output will stop short of it's limit and a portion of the output range will be unavailable no matter how you move the stick. That's Stopping Short.
The solution is to handle offsets a little differently by giving stick input priority over them. Compute the distance the stick is from the end of its travel and...Continue Reading
Mixes are for mixing, inputs are for selecting.
It may be that you're performing operations on your Mixes page that could be done instead on your Inputs page. The Inputs page isn't just good for selecting rates and exponential for your sticks, you can move virtually any operation that consist solely of selecting, rather than mixing, to the Inputs page. This can be useful for removing clutter from your Mixes page and more evenly distributing your setup across the two pages, which both limit their number of lines to 64.
Here's an example from my glider setup, where I use TrmT to adjust reflex and camber in four different flight modes. It started out on the Mixes page:
Channel 10 was being read by the aileron and flap output channels with mix lines similar to this one (this is not exact):
This worked fine but my mix lines were starting to run short and I wanted to clean up the page, so I moved the operation to the Inputs page and added a "catchall" at the end to make sure that the input explicitly contributes a value of zero when not in a flight mode that incorporates reflex or camber:
Now, on the Mixes page I read the input with lines similar to this:
With this technique I've relocated quite a few of my mix lines to my Inputs page, and now I have plenty of space open for new mixes.
It may be that you're performing operations on your Mixes page that could be done instead on your Inputs page. The Inputs page isn't just good for selecting rates and exponential for your sticks, you can move virtually any operation that consist solely of selecting, rather than mixing, to the Inputs page. This can be useful for removing clutter from your Mixes page and more evenly distributing your setup across the two pages, which both limit their number of lines to 64.
Here's an example from my glider setup, where I use TrmT to adjust reflex and camber in four different flight modes. It started out on the Mixes page:
Code:
CH10(RfxCam) TrmT Weight(+50%) Flight mode(Zoom) Offset(50%) [Zoom]
+= TrmT Weight(+25%) Flight mode(Speed) Offset(25%) [Speed]
+= TrmT Weight(+25%) Flight mode(Thermal) Offset(-25%) [Thermal]
+= TrmT Weight(+50%) Flight mode(Launch) Offset(-50%) [Launch]
Code:
CH01 (RtAil) CH10 Weight(+100%)
Code:
[I4]RxCm TrmT Weight(+50%) Flight mode(Zoom) Offset(50%) [Zoom]
TrmT Weight(+25%) Flight mode(Speed) Offset(25%) [Speed]
TrmT Weight(+25%) Flight mode(Thermal) Offset(-25%) [Thermal]
TrmT Weight(+50%) Flight mode(Launch) Offset(-50%) [Launch]
MAX Weight(0%) [Default]
Code:
[I4]RxCm Weight(+100%)
Presenting Miami Mike's F3J/TD Glider Simulator for the FrSky Taranis X9D
Instructions for downloading, installing, and running glidsim.lua
Please post questions, comments, suggestions, bug reports, and general discussion of the glider simulator in the comment section below.
Instructions for downloading, installing, and running glidsim.lua
- Click here or the link below to download glidsim.txt.
- Rename the file to "glidsim.lua".
- Store it in your OpenTX Companion SDCARD folder and on your radio's SD card, under /SCRIPTS/TELEMETRY.
- Open an eepe file containing an F3J/TD glider setup, and open the glider for editing.
- Select the Telemetry tab, scroll to the bottom, and select an unused Telemetry screen tab.
- For Custom Screen Type select Script, then glidsim.
- Select Simulate at the bottom of the page.
- Select the Taranis Simulator tab.
- On the Taranis simulator, long-press the PAGE button to get to the Glider Simulator page.
- To set flap offset, move the radio controls to their flap-neutral positions and press PLUS (+).
- To switch between cross-tail and v-tail, Press MINUS (-).
- To exit the simulator, long-press EXIT.
- After setting up all of your gliders for glidsim.lua, be sure to save the modified eepe file.
- When running the simulator on your radio, move the controls to their flap-neutral positions before switching on, clearing a switch warning, or selecting a model. Flap neutral will be set automatically when a model has finished loading.
Please post questions, comments, suggestions, bug reports, and general discussion of the glider simulator in the comment section below.
Taranis: glidersim.lua - A New Tool For Setting Up Your Glider
This is a preview of my new Glider Simulator, which runs on the Taranis or OpenTX Companion just like a telemetry script. It's not quite ready for release because I still have to add V-tail support, but here's a demo of the X-tail mode. As soon as I get it finished and well-tested I'll release it to everyone for free. I think you'll find it to be a valuable aid to F3X/TD glider setup, especially with its clipping indication feature.
Clipping means that a control has reached a position such that even if more movement in the same direction is available, it won't do anything. It doesn't mean that any stress or damage is taking place because the Outputs stage prevents that, but I still consider it to be undesirable and have eliminated it in my own setups. I'll post more on that later, but meanwhile, enjoy the demo.
This is a preview of my new Glider Simulator, which runs on the Taranis or OpenTX Companion just like a telemetry script. It's not quite ready for release because I still have to add V-tail support, but here's a demo of the X-tail mode. As soon as I get it finished and well-tested I'll release it to everyone for free. I think you'll find it to be a valuable aid to F3X/TD glider setup, especially with its clipping indication feature.
Clipping means that a control has reached a position such that even if more movement in the same direction is available, it won't do anything. It doesn't mean that any stress or damage is taking place because the Outputs stage prevents that, but I still consider it to be undesirable and have eliminated it in my own setups. I'll post more on that later, but meanwhile, enjoy the demo.
| glidersim.lua - A glider simulator for the Taranis screen (11 min 0 sec) |
Here are some examples of experiments you can do to determine the order in which data is processed by the OpenTX Inputs and Mixes pages:
Experimental Testing of OpenTX Data Flow
Experimental Testing of OpenTX Data Flow
- Set up a new model memory for testing.
- Create a single input on the Inputs page.
Code:[I1] Ail Weight(+100%)
- Create a single mix on the Mixes page.
Code:[I1]Ail Weight (+100%)
- On the Outputs page, ensure that all channels are set to the defaults of
- Subtrim = 0.0%
- Min = -100%
- Max = +100%
- Direction = ---
- Curve = ---
- Subtrim = 0.0%
- Test the basic setup.
- Start Companion simulator and move the aileron stick left and right. Observe that the CH01 indicator moves left and right from -100% to +100%.
- Exit the simulator.
- Start Companion simulator and move the aileron stick left and right. Observe that the CH01 indicator moves left and right from -100% to +100%.
- Create a special test curve.
- On the Curves page, create a 7-level, 12-point, stair-step curve.
- Select Curve 1.
- Select 12 points.
- Select Custom X.
- Enter these values:
- Select Curve 1.
- On the Curves page, create a 7-level, 12-point, stair-step curve.
- Create a single input on the Inputs page.
- You are now set up to perform experiments to determine the order in which data are processed in the Inputs and Mixes pages by OpenTX.
- Testing the Data Flow in Mixes
- Experiment #1: In Mixes, which is processed first, Weight or Curve?
- On the Mixes page, copy the mix from CH01 to CH02.
- Add Curve 1 to the CH02 mix:
Code:CH02 [I1]Ail Weight(+100%) Curve(1)
- Start Companion simulator and move the aileron stick left and right. Observe how the CH02 indicator steps through a range of 7 discrete levels as it moves left and right from -100% to +100%.
- Exit the simulator.
- On the Mixes page, copy the mix from CH01 to CH02.
- Experiment #1: In Mixes, which is processed first, Weight or Curve?
Sticky:
Taranis: The Kapow Trigger!
Using Logic Symbols and Digital Electronic Schematic Diagrams as An Aid to Understanding and Designing Logical Switch Setups
I've found that it can be useful to draw schematic diagrams of equivalent digital electronic circuits for logical switch setups that I'm designing or analyzing.
For a fairly simple example, here's the code that activates and deactivates the CAL (Calibrate) mode in Mike Shellim's F3J/TD setups:
L3 is the output. When L3 is true the radio is in CAL mode (Flight Mode 1).
Here's what it looks like when translated into a schematic diagram:
To enter CAL mode the stick is held in the lower-left corner (L5 is true) and the spring-loaded SH switch is pulled (SH↓). To exit CAL mode, SH is pulled (SH↓) with the stick not in the lower-left corner.
An interesting fact about this arrangement is that the combination of L2 and L3 serve virtually the same function as a sticky. This is much easier to see in the schematic diagram than in the radio programming.
So why not use a sticky instead and save a logical switch?
Here's an alternate "circuit":
...Continue Reading
I've found that it can be useful to draw schematic diagrams of equivalent digital electronic circuits for logical switch setups that I'm designing or analyzing.
For a fairly simple example, here's the code that activates and deactivates the CAL (Calibrate) mode in Mike Shellim's F3J/TD setups:
L3 is the output. When L3 is true the radio is in CAL mode (Flight Mode 1).
Here's what it looks like when translated into a schematic diagram:
To enter CAL mode the stick is held in the lower-left corner (L5 is true) and the spring-loaded SH switch is pulled (SH↓). To exit CAL mode, SH is pulled (SH↓) with the stick not in the lower-left corner.
An interesting fact about this arrangement is that the combination of L2 and L3 serve virtually the same function as a sticky. This is much easier to see in the schematic diagram than in the radio programming.
So why not use a sticky instead and save a logical switch?
Here's an alternate "circuit":
...Continue Reading
Add Bluetooth to silently monitor your Taranis telemetry!
Bluetooth transmitter from Amazon
Bluetooth receiver from Amazon
If the receiver is unavailable, here's a search for similar items.
This one looks good.
Here's the Bluetooth transmitter mounted to the back of the module compartment cover with double-
sided sticky tape. There's a notch cut out at the bottom corner for the audio cable to pass through.
...Continue Reading
Bluetooth transmitter from Amazon
Bluetooth receiver from Amazon
If the receiver is unavailable, here's a search for similar items.
This one looks good.
Here's the Bluetooth transmitter mounted to the back of the module compartment cover with double-
sided sticky tape. There's a notch cut out at the bottom corner for the audio cable to pass through.
...Continue Reading
Here are my current Taranis X9D control assignments for sailplanes:
My radios have 3-position switches in place of S1 and S2, as described in Taranis: Change S1 & S2 to Switches. The switch positions are labeled S1↑, S1-, S1↓, S2↑, S2-, and S2↓.
My model memory setups are based upon Mike Shellim's F3J/TD Version 2, with substantial modifications, some of which are adopted from his newer F3J/TD Version 3 setup. You can find his competition glider setups at http://www.rc-soar.com/opentx/setups/f3j/.
Description:
My radios have 3-position switches in place of S1 and S2, as described in Taranis: Change S1 & S2 to Switches. The switch positions are labeled S1↑, S1-, S1↓, S2↑, S2-, and S2↓.
My model memory setups are based upon Mike Shellim's F3J/TD Version 2, with substantial modifications, some of which are adopted from his newer F3J/TD Version 3 setup. You can find his competition glider setups at http://www.rc-soar.com/opentx/setups/f3j/.
Description:
- SE Different Functions for Pure Glider and Motor Glider Versions
- Pure Glider Version - Flight Modes For Winch Launching. Flap stick must be in full-up position.
- SE↑ Zoom mode. A separate elevator rate for Zoom mode is included on the Inputs page.
- SE- Glide (Goes to the flight mode selected by switch SA.)
- SE↓ Launch mode. Uses a separately adjustable combi mix that reads the aileron stick directly and is independent of aileron rates.
- Motor Glider Version - Motor Control Motor must be armed.
- SE↑ motor full power
- SE- motor half power
- SE↓ motor off. SE must be in this position before motor arming is possible.
- Pure Glider Version - Flight Modes For Winch Launching. Flap stick must be in full-up position.
- SF Select Landing Mode When the flap stick is moved away from the top position either Flap mode or Crow mode is activated, depending upon the position of SF.
- SF↑ Flap mode (flaps only) with separate elevator compensation curve and weight setting.
- SF↓ Crow mode (flaps down, ailerons up)
If 3-position switches (short or long) are wired in parallel with the S1 and S2 potentiometers ("pots"), the pots are left in their center positions (very important), insulated, and stored inside the radio, and the switches are installed in their places, the following six additional switch functions will be available:
S1↑ S1− S1↓ S2↑ S2− S2↓ (Of course these designations won't show up on your radio screen or in Companion but they can be useful in your programming notes.)
Decoding S1↑ and S1↓ with Logical Switches:
If S1− represents a default setting then it might not need to be specifically decoded, otherwise it can be decoded with a third Logical Switch:
The code for S2 is similar:
To wire a 3-position switch in parallel with a pot, use short insulated jumper wires to connect the top terminal of the pot to the top terminal of the switch, the center terminal of the pot to the center terminal of the switch, and the bottom terminal of the pot to the bottom terminal of the switch. Remember that the pot has to stay connected even though it won't be accessible, and it has to be set to the center detent position.
If you want to reverse the modification later it won't be necessary to disconnect or remove the switch. Just set it to its center position, insulate it, store it away inside the radio, and put the pot back where it used to be. Remember that in either case the control that's not being used must remain set to its center position.
S1↑ S1− S1↓ S2↑ S2− S2↓ (Of course these designations won't show up on your radio screen or in Companion but they can be useful in your programming notes.)
Decoding S1↑ and S1↓ with Logical Switches:
Code:
L1 a~x S1 100 ---- 0.0 0.0 L1 = S1↑ L2 a~x S1 -100 ---- 0.0 0.0 L2 = S1↓ These two Logical Switches may be reversed, depending upon which way the 3-position switch is installed in your radio.
Code:
L3 AND !L1 !L2 ---- 0.0 0.0 L3 = S1−
Code:
L4 a~x S2 100 ---- 0.0 0.0 L4 = S2↑ L5 a~x S2 -100 ---- 0.0 0.0 L5 = S2↓ L6 AND !L4 !L5 ---- 0.0 0.0 L6 = S2−
If you want to reverse the modification later it won't be necessary to disconnect or remove the switch. Just set it to its center position, insulate it, store it away inside the radio, and put the pot back where it used to be. Remember that in either case the control that's not being used must remain set to its center position.
