You signed in with another tab or window. Reload to refresh your session.You signed out in another tab or window. Reload to refresh your session.You switched accounts on another tab or window. Reload to refresh your session.Dismiss alert
* Initial write-up
* Images added
* minor tweaks
* arming requirement tweaks
* update Arming V4 text
* fix typo
* Wording updates, Additional Notes
* The Importance of Arming
* add Rotorflight to wordlist
* Wording update for consistency
* Missed one
* Reworded sections, Admonitions and Table updates
* Spelling Correction
* Added Ch5 source when not in Full Res
* Added Mickey's Graphic
* Include CH14 arm flag
---------
Co-authored-by: Michael <101.37584@germanynet.de>
Co-authored-by: Bryan Mayland <bmayland@capnbry.net>
Copy file name to clipboardExpand all lines: docs/quick-start/transmitters/tx-prep.md
+79-2Lines changed: 79 additions & 2 deletions
Display the source diff
Display the rich diff
Original file line number
Diff line number
Diff line change
@@ -310,9 +310,86 @@ ExpressLRS uses the CRSF serial protocol to communicate between the transmitter
310
310
311
311
Set the Internal RF module to Off, and set the External RF module to CRSF protocol, as any External RF module requires.
312
312
313
+
### Version 4.0 Arming Options
314
+
315
+
Starting with ExpressLRS v4.0.0 an additional Arming method is introduced.
316
+
317
+
!!! info "What's so important with Arming?"
318
+
ExpressLRS checks for a switch position to determine what safeguards or performance boosts will be active to prevent disconnections, especially when the receiver is on a flying/moving RC aircraft or vehicle. See [The Importance of Arming](../../software/switch-config.md#whats-so-important-with-arming) for an in-depth explanation.
319
+
320
+
The traditional Arming method, using Channel 5 (Aux1) driven by EdgeTX Mixer's Channel 5 is the default and is still encouraged to be used by majority of FPV pilots using Betaflight, INAV or Ardupilot (and their respective derivatives like Emuflight, Rotorflight, etc.) more so when using non-Full Res modes. This is because you are still required to have a mode for arming using an Aux channel. This will now be called **Arm using CH5** and is set by EdgeTX (2.11 or newer) as default.
See the [next section](#switches-and-aux-channels) on how to configure your Channel Mixes.
327
+
328
+
!!! Tip "**Arm using Switch** Requirements"
329
+
Arm using Switch **requires** EdgeTX version 2.11 or newer and ExpressLRS version 4.0 or newer. If you cannot find the "Arm using" option you need to update your EdgeTX and/or ExpressLRS firmware.
330
+
331
+
The alternative Arming method, **Arm using switch** is more suited to users who aren't familiar with drone-side arming concept, or primarily those using PWM receivers. **Arm using Switch** is performed by user selected sources, e.g. physical or logical switches, anything EdgeTX offers as a source. It works in all packet rates and switch modes, with varying channel reactions, explained below.
332
+
333
+
When in Full Res modes, Channel 5 will behave as any of the other full proportional channels. This means:
334
+
335
+
- No need to remap Output 5 with other channel input sources.
336
+
- No need to skip Output 5 on your PWM receivers if you don't know how to remap outputs.
337
+
- SBUS-dependent Stabilizer gain control requiring Channel 5 will work now.
338
+
- Flight Modes requiring Channel 5 will also work.
339
+
340
+
When not in Full Res mode, Channel 5 will behave as a 2-position switch, but it will not use the configured Mix for Channel 5 and instead use the configured arming switch as the Channel source.
341
+
342
+
!!! Note "Hybrid and Wide Switch Modes"
343
+
With **Arm using Switch** selected, the min and max values for Channel 5 will still come from the switch you have selected for arming, and will still function as 2-position switch. It will override the model's Channel 5 Mixes Configuration.
344
+
345
+
!!! info "Channel 14 Behavior"
346
+
To help receivers determine the Armed state, Channel 14 gets the channel values for the switch configured for arming in Hybrid, Wide and 8ch/12ch Full Res switch modes.
347
+
348
+
**Arm using Switch** can be enabled in the EdgeTX Internal/External RF Model Setup menu by changing “Arm using” to “Switch”.
349
+
350
+
<figuremarkdown>
351
+
352
+
</figure>
353
+
354
+
#### How to set up Arming Mode Switch:
355
+
356
+
1. Press the ++"MDL"++ Key.
357
+
- Older Radios or those with only one Menu Key will need to short-press the ++context-menu++ Key to access the Model Menu.
358
+
- Consult your Radio User's Manual on how to get to the Model Menu.
359
+
2. Press the ++"PAGE"++ Key until you reach the Model Setup Page.
360
+
- On radios with Colored screens, this should be the first page when you activate the Model Menu.
361
+
- On radios with Monochrome screens, this should be the second page upon activating the Model Menu.
362
+
3. Scroll down until you reach the Internal or External RF settings, depending on which module you want to use for this model.
363
+
- Color screen radios provide separate pages for these.
364
+
- On Monochrome screens, the options are all in one page.
365
+
4. Short-press the scroll-wheel button or press the ++enter++ Key and change the setting to "Switch". This option will not show up for External RF unless an External ExpressLRS Module is being detected by the handset.
6. Select the next option to set your arming switch.
381
+
6. Press the ++enter++ Key and use the scroll-wheel to set your new arming switch. It can be any switch on the radio, a Logical Switch or any source. You can also flick the physical switch on the radio to set it.
7. Press the ++enter++ Key once more to set the switch.
388
+
8. Press ++"RTN"++ Key once you're done with the rest of your changes.
389
+
313
390
### Switches and Aux Channels
314
391
315
-
By default, a fresh model does not have any Aux Channels configured (Aux channels start from Ch5, with the first 4 Channels assigned to your joysticks). If moving any of the switches in your radio doesn't affect your Modes in Betaflight or INAV, this is one of the main reasons. So let's get this sorted out!
392
+
By default, a fresh model does not have any Aux Channels configured (Aux channels start from Ch5, with the first 4 Channels assigned to your joysticks/gimbals). If moving any of the switches in your radio doesn't affect your Modes in Betaflight or INAV, this is one of the main reasons. So let's get this sorted out!
316
393
317
394
1. Press the ++"MDL"++ Key.
318
395
- Older Radios or those with only one Menu Key will need to short-press the ++context-menu++ Key to access the Model Menu.
@@ -346,4 +423,4 @@ By default, a fresh model does not have any Aux Channels configured (Aux channel
|| Packet <br>Rates | 50 thru <br>F1000 | 50 thru <br>F1000 | Full Res <br>Only | Full Res <br>Only | Full Res <br>Only |
34
+
35
+
<small>* v4.0 changes, with the introduction of the new arming methods</small>
34
36
35
37
### Switch Position / Channel Resolution
36
38
@@ -45,10 +47,12 @@ This table summarizes the switch configuration modes, available channel switch p
45
47
46
48
47
49
!!! warning "WARNING"
48
-
**Put your arm switch on AUX1**, and set it as **~1000 is disarmed, ~2000 is armed**.
50
+
IF you're using `Arm using CH5`, **put your arm switch on AUX1**, and set it as **~1000 is disarmed, ~2000 is armed**.
49
51
50
-
!!! note
51
-
If using a receiver with PWM outputs and you would like to use the PWM output 5 on the receiver for a servo, gear, etc. Go into the WiFi interface of the receiver and map any of the other channels to PWM Output 5. Please always still use AUX1 for the 2-pos Arm switch.
52
+
!!! note "ExpressLRS 3.x PWM output 5"
53
+
If using a receiver with PWM outputs and you would like to use the PWM output 5 on the receiver for a servo, gear, etc. Go into the WiFi interface of the receiver and map any of the other channels to PWM Output 5. Mixer Channel 5 is still going to be used for arming the TX module, and will be a 2-position channel.
54
+
55
+
No longer needed starting with ExpressLRS 4.x. Select one of the Full Res modes and Channel 5 will be a full proportional channel, like the others.
52
56
53
57
### Channel Update Rate versus Packet Rate
54
58
@@ -108,11 +112,19 @@ If using ArduPilot in **Wide** mode you will see that the channel outputs don't
108
112
109
113
These switch modes come in three flavors based on the number of output channels you would like and are only available on packet rates of 100Hz Full and 333Hz Full.
110
114
111
-
1.**8ch** - Channels 1 to 4 and Channels 6 to 9 are sent 10-bit, at the selected Packet Rate, along with Channel 5 (AUX1) in 1-bit (2-position) for Arming.
115
+
=== "Version 4.0 Changes"
116
+
1. **8ch** - Channels 1 to 8 are sent 10-bit, at the selected Packet Rate.
117
+
118
+
2. **16ch Rate/2** - All the Channels are sent 10-bit but at half rate.
119
+
120
+
3. **12ch Mixed** - Channels 1 to 4 are sent 10-bit at the selected Packet Rate. Channels 5 to 12 are then sent at 10-bit but at half rate.
112
121
113
-
2.**16ch Rate/2** - All the Channels are sent 10-bit but at half rate.
122
+
=== "Version 3.x"
123
+
1. **8ch** - Channels 1 to 4 and Channels 6 to 9 are sent 10-bit, at the selected Packet Rate, along with Channel 5 (AUX1) in 1-bit (2-position) for Arming.
114
124
115
-
3.**12ch Mixed** - Channels 1 to 4 are sent 10-bit with Channel 5 (AUX1) in 1-bit (2-position) for Arming at the selected Packet Rate. Channels 6 to 13 are then sent at 10-bit but at half rate.
125
+
2. **16ch Rate/2** - All the Channels are sent 10-bit but at half rate.
126
+
127
+
3. **12ch Mixed** - Channels 1 to 4 are sent 10-bit with Channel 5 (AUX1) in 1-bit (2-position) for Arming at the selected Packet Rate. Channels 6 to 13 are then sent at 10-bit but at half rate.
116
128
117
129
All of these 10-bit or 1024 positions are mapped to PWM 885us to 2115us (1 bit = 1.23046875us) in what is called **"CRSF Extended Limits"**
118
130
@@ -122,48 +134,59 @@ All of these 10-bit or 1024 positions are mapped to PWM 885us to 2115us (1 bit =
122
134
123
135
## FAQ
124
136
125
-
### <spanclass="custom-heading"data-id="1">Why do you keep saying "*put arm on AUX1*"?</span>
137
+
### <spanclass="custom-heading"data-id="1">What's so important with Arming?</span>
126
138
127
-
??? Note "Why do you keep saying "*put arm on AUX1*"?"
128
-
For safety and performance reasons.
139
+
??? Note "What's so important with Arming?"
129
140
130
141
**SAFETY**
131
142
132
-
AUX1 is sent with every packet going out, this is the most reliable way to be able to tell your model to disarm. If your arm switch is on another aux channel, it may be several packets before that switch is transmitted, and there's no guarantee that the RX will actually receive that packet. There's a non-trivial chance your model **may not ever disarm** if the link quality is low and it just so happens that the packet containing the arm switch is getting missed every time. Forcing the arm switch into every packet on AUX1 means that if **any** packet is received by ExpressLRS, it will disarm your model, not just a less than 1-in-7 chance.
143
+
Your transmitter and receiver act differently when “armed” and when “disarmed”. When disarmed, the transmitter and receiver are free to adjust their communication in order to make the LUA and other configuration operations more responsive. When "disarmed", everything will appear to be working appropriately but none of the safeguards will be in place and performance will not be what you expect.
133
144
134
-
It also protects against unintentional disarms caused by a corrupt packet changing the value of the arm switch to disarmed. Betaflight requires that 4x "disarm" commands are received before disarming to guard against this possibility. With arm on AUX1, a single corrupt packet can not disarm your model. With arm on AUX2-8, the one corrupt switch value will be sent 6 times before the value is refreshed, but the flight controller would have already disarmed by that point.
145
+
!!! warning inline end "No Safeguards"
146
+
Without these safeguards, these actions can interrupt OTA transmission causing disconnections and ultimately failsafe.
135
147
136
-
Your transmitter and receiver also act differently when “armed” and when “disarmed”. When disarmed, the transmitter and receiver are free to adjust their communication in order to make the LUA and other configuration operations more responsive. When "disarmed", everything will appear to be working appropriately but none of the safeguards will be in place and performance will not be what you expect.
148
+
When `Armed`, these safeguards are applied:
137
149
138
-
When `IsArmed` is enabled, these safeguards are applied:
139
-
140
-
- All "Button" inputs are disabled
141
-
- All "Joystick" (5-way buttons) are disabled
150
+
- All "Button" inputs on external TX modules are disabled
151
+
- All "Joystick" (5-way buttons) on external TX modules are disabled
142
152
- Bump to Share is disabled
143
153
- VTX Admin is disabled
144
154
- Integrated VTX channel change is disabled
145
155
146
156
**PERFORMANCE**
147
157
148
-
When `IsArmed` is enabled, these performance features are activated:
158
+
When `Armed`, these performance features are activated:
149
159
150
160
- Dynamic Power is fully enabled
161
+
- Missing a Telemetry Packet will push the Transmission Power to Max
162
+
- Sudden disconnection or Failsafe will push the Transmission Power to Max
151
163
- Race telemetry mode turns telemetry off
164
+
- All packets are then dedicated to control packets.
152
165
- Some thermal-based fan controls are enabled
166
+
- Available on select TX modules
167
+
168
+
### <spanclass="custom-heading"data-id="2">Why do you keep saying "*put arm on AUX1*"?</span>
169
+
170
+
??? Note "Why do you keep saying "*put arm on AUX1*"?"
171
+
For safety and performance reasons.
172
+
173
+
AUX1 is sent with every packet going out, this is the most reliable way to be able to tell your model to disarm. If your arm switch is on another aux channel, it may be several packets before that switch is transmitted, and there's no guarantee that the RX will actually receive that packet. There's a non-trivial chance your model **may not ever disarm** if the link quality is low and it just so happens that the packet containing the arm switch is getting missed every time. Forcing the arm switch into every packet on AUX1 means that if **any** packet is received by ExpressLRS, it will disarm your model, not just a less than 1-in-7 chance.
174
+
175
+
It also protects against unintentional disarms caused by a corrupt packet changing the value of the arm switch to disarmed. Betaflight requires that 4x "disarm" commands are received before disarming to guard against this possibility. With arm on AUX1, a single corrupt packet can not disarm your model. With arm on AUX2-8, the one corrupt switch value will be sent 6 times before the value is refreshed, but the flight controller would have already disarmed by that point.
153
176
154
-
Arming is an extremely important part of the performance of the control link. Please use Aux 1 / Chan 5 as indicated. Also keep in mind that for ExpressLRS, ~1000us is the **disarmed** state and ~2000us is the **armed** state.
177
+
Please use Aux 1 / Chan 5 with ~1000us as the **disarmed** state and ~2000us as the **armed** state.
155
178
156
-
### <spanclass="custom-heading"data-id="2">I use a 3-pos switch for arm, this software is unusable?</span>
179
+
### <spanclass="custom-heading"data-id="3">I use a 3-pos switch for arm, this software is unusable?</span>
157
180
158
181
??? Note "I use a 3-pos switch for arm, this software is unusable?"
159
182
Good news, you can still use a 3-position switch to arm! However, you will need to adjust the model input / mixer settings for AUX1 in EdgeTX / OpenTX to remap the switch to be 2-position / on-off switch. If your 3-position arm switch had a second function as well, such as enabling Blackbox, just use one of the other channels to send the same switch on a second channel using the model input / mixer settings EdgeTX / OpenTX.
160
183
161
-
### <spanclass="custom-heading"data-id="3">What about "Normal" one bit switch mode?</span>
184
+
### <spanclass="custom-heading"data-id="4">What about "Normal" one bit switch mode?</span>
162
185
163
186
??? Note "What about "Normal" one bit switch mode?"
164
187
In version 1.0 of ExpressLRS, there was also a switch mode called "Normal" where there were eight 1-position switches sent in every packet. This mode was removed in version 2.0 due to its unpopularity and the flash space was used for other features. Please use Hybrid or Wide modes and all of the high performance packet rates.
165
188
166
-
### <spanclass="custom-heading"data-id="4">Every time I change switch mode in Lua, it changes back! Is my transmitter broken?</span>
189
+
### <spanclass="custom-heading"data-id="5">Every time I change switch mode in Lua, it changes back! Is my transmitter broken?</span>
167
190
168
191
??? Note "Every time I change switch mode in Lua, it changes back! Is my transmitter broken?"
169
192
If the Lua loads then you know its communicating with your transmitter. However, the switch mode can only be changed when a receiver is not connected and makes it appear as if the changes are not saving. This is done to ensure consistency between the RX and TX interpretation of the switch data being actively transmitted. This is a safeguard. Power down your receiver, wait for the "Telemetry Lost" callout, and the switch mode change will stick / save. The receiver will talk to the transmitted when it is powered up to handshake on the new settings.
0 commit comments