DIY-Multiprotocol-TX-Module/docs/Models.md

Model Setup

This is the page to document model or receiver specific setup instructions.

The Deviation project (on which this project was based) have a useful list of models here.

Syma X5C

Channel Map

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
A	E	T	R	FLIP	RATES	PICTURE	VIDEO

Binding

There are no special binding instructions. The model powers up in Autobind mode and expects the bind sequence from the transmitter within the first 4-5 seconds.

Tx Setup

A basic 4-channel setup works perfectly, but some improvements are possible:

Setting up a switch to Flip

1. Choose your "Rates" switch - typically the momentary TRN switch
2. In the Mixer create an entry for CH5
3. Edit this line as follows:
   • er9X: Source: sTRN, Weight 100 (or whatever switch you selected)
   • OpenTx: Source: SH, Weight 200 (or whatever switch you selected)

Setting up a swich for high rates

1. Choose your "Rates" switch
2. In the Mixer create an entry for CH6
3. Edit this line as follows:
   • er9X: Source: sTHR, Weight 100 (or whatever switch you selected)
   • OpenTx: Source: SF, Weight 200 (or whatever switch you selected)

When the switch is in the rear position the rates will be standard, when the switch is forward rates will be high. There is no need to move the throttle stick to the full up and full down position as with the standard controller.

Setting up Idle-up

One of the most annoying functions on the Syma X5C is that the motors stop when the throttle is pulled back. This can be fixed by implmenting Idle-up on the transmitter (think of this as a very simple version of the Betaflight "Air Mode"). Idle up will ensure that even when the throttle is all the way down, a minimum command is passed to the motor to keep them spinning and to activate the stabilization.

To do this:

1. Decide on a switch you will use to activate Idle up
2. In the mixer menu add a line under Throttle and mix in a value of between 4 and 6 to be added to the throttle value if the switch is activated. What this does is effectively prevents the throttle from going down to less than this value.
3. When you want to fly in "idle-up" mode flick the switch and your stabilization will always be active.
4. Remeber to switch off idle-up as soon as the quad lands (or crashes - to avoid damage to the motors)

Inductrix (Horizon Hobby)

Binding

For telemetry enabled modules, you should just let the remote autodetect the settings. Otherwise choose DSMX 22ms with 6ch or 7ch. To bind the model, keep the transmitter off, power on the Inductrix. Wait until it flashes fast and then power up the Tx and use Bind.

Tx Setup

Remember that 100% on your transmitter using the MULTI-Module corresponds to 125% on the DSM receiver side. On some functions sending 100% will confuse the model. Conversely 80% on your Tx is interpreted to be 100% at the model. Consider this when implementing the suggestions below.

Throttle

For Inductrix FPV you might need to adjust the lower end of throttle to be a higher than default, otherwise motors will be spinning on minimal throttle. One way to do this is to set the throttle to 80% output (100% of DSM output) and then to enable the Throttle Idle Trim Only under the Model Setup menu. See image below:

Acro and Level Mode

Setup channel 6 with a momemtary button or switch (e.g. SH on the Taranis) and use that switch to switch between modes. Set the output to somewhere between 40% to 60% for best results.

An addition consideration when flying in Acro mode is to reduce stick sensitivity and to add some expo. The screens below show one way of doing this. Customize to your needs.

Inputs Screen

The follwing INPUTS screen shows one potential setup to introduce expo for Acro mode. The activation of the expo on Roll, Pitch and Yaw is when the SG switch is not in the back position. Add to taste.

Aileron Rates attached to Switch !SG-up

The next screen shows and example of how the expo (50%) was set up on the stick input and how it is activated by !SG-up:

Mixer Menu

The next screen shows the mixer menu with the mode change on momentary switch SH and High-Low rates on switch SC:

Cheerson CX-20 / Quanum Nova

Channel Map

CH1	CH2	CH3	CH4	CH5	CH6	CH7
A	E	T	R	MODE	AUX1	AUX2

Binding

The Rx powers up in binding mode so the transmitter should be set to autobind. If the Tx signal is lost due to power-off or going out of range the Rx will not re-bind, and requires power-cycling before it will bind again.

Tx Setup

AETR are simple +100% mixes. Note that the model expects Elevator (CH2) to be reversed, which is handled in the module firmware, so no need to reverse it on the Tx.

Flight modes

CH5 is used to transmit the flight mode to the APM flight controller by setting the output to a value in a pre-defined range. The original Tx uses a 3-pos switch (SWA) and a 2-pos switch (SWB) to achieve six different combinations, but only five are used - with SWA at 0, 1500 is sent when SWB is at 0 and 1, leaving flight mode 3 unused. However, in the stock CX-20 flight controller settings, both flight mode 3 and 4 are set to the same flight mode, meaning we can configure our new Tx settings to send a value for mode 3 without changing the standard flight mode behaviour. Afterwards, you can optionally use Mission Planner to assign a new flight mode to mode 3 or mode 4, or reconfigure them altogether.

The values, modes, and switch positions for the stock Tx are:

Mode	Stock Tx PWM Value	CX-20 Mode	SWA	SWB
1	1100	Return to Home	2	0
2	1300	Altitude Sensor	2	1
3
4	1500	Manual	0	0 or 1
5	1700	Direction Lock	1	1
6	1900	Stable	1	0

NB The CX-20 uses flight mode names which are different to the standard APM flight mode names. The CX-20 modes map to APM modes as follows:

CX-20 Mode	APM Mode
Manual	Stabilize
Stable	Loiter
Direction Locked	Simple
Altitude Sensor	Altitude Hold
Return to Home	RTL (Return to Launch)

We need to set the Tx up to output these values on CH5 (or very similar values - more information, including the PWM width ranges is documented in the Arducopter Wiki).

One easy way to acheive this is to configure six logical switches mapped to two physical switches, for example the 3-way ID switch and the AIL D/R switch, then configure the logical switches to activate a flgiht mode and to apply a specific weight to the CH5 output.

To simply map the old Tx modes to the new Tx using the same switch positions, use the following configuration. The stock SWA switch is replaced with the ID0/1/2 switch, SWB is replaced with the AIL D/R switch.

Logical switches:

Switch	Function	V1	V2
L. Switch 1	AND	ID2	!AIL
L. Switch 2	AND	ID2	AIL
L. Switch 3	AND	ID0	!AIL
L. Switch 4	AND	ID0	AIL
L. Switch 5	AND	ID1	AIL
L. Switch 6	AND	ID1	!AIL

light modes (using CX-20 names):

Mode	Name	Switch
1	RTL	L1
2	AltSen	L2
3	Manual	L3
4	Manual	L4
5	DirLock	L5
6	Stable	L6

Mixer setup:

Channel	Weight	Source	Switch	Multiplex
CH5	-80%	HALF	L1	REPLACE
-40%	HALF	L2	REPLACE
-20%	HALF	L3	REPLACE
+0%	HALF	L4	REPLACE
+40%	HALF	L5	REPLACE
+80%	HALF	L6	REPLACE

NB The weight values in this table will get you in the ball park, and will most likely work fine. Because transmitters can vary they should be double-checked in the Mission Planer Radio Calibration screen, and tweaked as necessary.

CH6 and CH7

CH6 and CH7 can be assigned to switches or pots to provide additionaly functionality such as PID tuning, gimbal control, or APM auto-tune or auto-land.

Replicating the stock setup of two pots, you would assign:

Channel	Weight	Source	Multiplex
CH6	+100%	P1	ADD
CH7	+100%	P3	ADD

Full Mixer Setup

Channel	Source	Weight	Switch	Multiplex
CH1	+100%	Aileron
CH2	+100%	Elevator
CH3	+100%	Throttle
CH4	+100%	Rudder
CH5	-80%	HALF	L1	REPLACE
-40%	HALF	L2	REPLACE
-20%	HALF	L3	REPLACE
+0%	HALF	L4	REPLACE
+40%	HALF	L5	REPLACE
+80%	HALF	L6	REPLACE
CH6	+100%	P1
CH7	+100%	P3

Once you have configured the mixes you should connect Mission Planner to your CX-20 and use the Radio Calibration screen to verify that the channels are correctly assigned, and that the flight modes are correct. Mission planner will give the exact PWM value on CH5, allowing the weights to be adjusted if needed.