Protocols_Details.md

Protocols details

Here are detailed descriptions of every supported protocols (sorted by RF modules) as well as the available options for each protocol.

If you want to see examples of model configurations see the Models page.

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

Useful notes and definitions

• Extended limits supported - A command range of -125%..+125% will be transmitted. Otherwise the default is -100%..+100% only.
• Channel Order - The channel order assumed in all the documentation is AETR. You can change this in the compilation settings. The module will take whatever input channel order and will rearrange them to match the output channel order required by the selected protocol.
• Italic numbers are referring to protocol/sub_protocol numbers that you should use if the radio (serial mode only) is not displaying (yet) the protocol you want to access.
• Autobind protocol:

1. The transmitter will automatically initiate a bind sequence on power up. This is for models where the receiver expects to rebind every time it is powered up. In these protocols you do not need to press the bind button at power up to bind, it will be done automatically. In case a protocol is not autobind but you want to enable it, change the "Autobind" (or "Bind at powerup" on OpenTX) setting to Y for the specific model/entry.
2. Enable Bind from channel feature:
   • Bind from channel can be globally enabled/disabled in _config.h using ENABLE_BIND_CH.
   • Bind from channel can be locally enabled/disabled by setting Autobind to Y/N per model for serial or per dial switch number for ppm.
   • Bind channel can be choosen on any channel between 5 and 16 using BIND_CH in _config.h. Default is 16.
   • Bind will only happen if all these elements are happening at the same time:
     • Autobind = Y
     • Throttle = LOW (<-95%)
     • Bind channel is going from -100% to +100%

• Additional notes:
  • It's recommended to combine Throttle cut with another button to drive the bind channel. This will prevent to launch a bind while flying...
  • Bind channel does not have to be assigned to a free channel. Since it only acts when Throttle is Low (and throttle cut active), it could be used on the same channel as Flip for example since you are not going to flip your model when Throttle is low... Same goes for RTH and such other features.
  • Using channel 16 for the bind channel seems the most relevant as only one protocol so far is using 16 channels which is FrSkyX. But even on FrSkyX this feature won't have any impact since there is NO valid reason to have Autobind set to Y for such a protocol.

Protocol selection in PPM mode

The protocol selection is based on 2 parameters:

• selection switch: this is the rotary switch on the module numbered from 0 to 15
  • switch position 0 is to select the Serial mode for er9x/ersky9x/OpenTX radio
  • switch position 15 is to select the bank
  • switch position 1..14 will select the protocol 1..14 in the bank X
• banks are used to increase the amount of accessible protocols by the switch. There are up to 5 banks giving acces to up to 70 protocol entries (5 * 14). To modify or verify which bank is currenlty active do the following:
  • turn on the module with the switch on position 15
  • the number of LED flash indicates the bank number (1 to 5 flash)
  • to go to the next bank, short press the bind button, this action is confirmed by the LED staying on for 1.5 sec

Here is the full protocol selection procedure:

1. turn the selection switch to 15
2. power up the module
3. the module displays the current bank by flashing the LED x number of times, x being between 1 and up to 5
4. a short press on the bind button turns the LED on for 1 sec indicating that the system has changed the bank
5. repeat operation 3 and 4 until you have reached the bank you want
6. power off
7. change the rotary switch to the desired position (1..14)
8. power on
9. enjoy

Notes:

• The protocol selection must be done before the module is turned on
• The protocol mapping based on bank + rotary switch position can be seen/modified at the end of the file _Config.h**

Serial mode

Serial mode is selected by placing the rotary switch to position 0 before power on of the radio.

You've upgraded the module but the radio does not display the name of the protocol you are loking for:

• ersky9x:
  • Place the file Multi.txt (which is part of the MPM source files) on the root of your SD card.
  • If the entry still does not appear or is broken, upgrade to version R222d2 or newer.
• OpenTX:
  • Upgrade to the latest version of OpenTX.
  • If still not listed, use the Custom entry along with the protocol and sub_protocol values indicated by the italic numbers under each protocol. You'll find a summary of the protocols and numbers to use in table below.

Available Protocol Table of Contents (Listed Alphabetically)

Protocol Name	Protocol Number	Sub_Proto 0	Sub_Proto 1	Sub_Proto 2	Sub_Proto 3	Sub_Proto 4	Sub_Proto 5	Sub_Proto 6	Sub_Proto 7	RF Module
Assan	24	ASSAN								NRF24L01
Bayang	14	Bayang	H8S3D	X16_AH	IRDRONE	DHD_D4				NRF24L01
Bugs	41	BUGS								A7105
BugsMini	42	BUGSMINI	BUGS3H							NRF24L01
Cabell	34	Cabell_V3	C_TELEM	-	-	-	-	F_SAFE	UNBIND	NRF24L01
CFlie	38	CFlie								NRF24L01
CG023	13	CG023	YD829							NRF24L01
Corona	37	COR_V1	COR_V2	FD_V3						CC2500
CX10	12	GREEN	BLUE	DM007	-	J3015_1	J3015_2	MK33041		NRF24L01
Devo	7	Devo	8CH	10CH	12CH	6CH	7CH			CYRF6936
DM002	33	DM002								NRF24L01
DSM	6	DSM2-22	DSM2-11	DSMX-22	DSMX-11	AUTO				CYRF6936
E01X	45	E012	E015	E016H						NRF24L01
ESky	16	ESky								NRF24L01
ESky150	35	ESKY150								NRF24L01
Flysky	1	Flysky	V9x9	V6x6	V912	CX20				A7105
Flysky AFHDS2A	28	PWM_IBUS	PPM_IBUS	PWM_SBUS	PPM_SBUS					A7105
FQ777	23	FQ777								NRF24L01
FrskyD	3	FrskyD								CC2500
FrskyV	25	FrskyV								CC2500
FrskyX	15	CH_16	CH_8	EU_16	EU_8					CC2500
FY326	20	FY326	FY319							NRF24L01
GD00X	47	GD_V1*	GD_V2*							NRF24L01
GW008	32	GW008								NRF24L01
H8_3D	36	H8_3D	H20H	H20Mini	H30Mini					NRF24L01
Hisky	4	Hisky	HK310							NRF24L01
Hitec	39	OPT_FW	OPT_HUB	MINIMA						CC2500
Hontai	26	HONTAI	JJRCX1	X5C1	FQ777_951					NRF24L01
Hubsan	2	H107	H301	H501						A7105
J6Pro	22	J6PRO								CYRF6936
KF606	49	KF606*								NRF24L01
KN	9	WLTOYS	FEILUN							NRF24L01
MJXq	18	WLH08	X600	X800	H26D	E010*	H26WH	PHOENIX*		NRF24L01
MT99xx	17	MT	H7	YZ	LS	FY805				NRF24L01
NCC1701	44	NCC1701								NRF24L01
OpenLRS	27									None
Potensic	51	A20								NRF24L01
Q2X2	29	Q222	Q242	Q282						NRF24L01
Q303	31	Q303	CX35	CX10D	CX10WD					NRF24L01
Redpine	50	FAST	SLOW							NRF24L01
SFHSS	21	SFHSS								CC2500
Shenqi	19	Shenqi								NRF24L01
SLT	11	SLT_V1	SLT_V2	Q100	Q200	MR100				NRF24L01
SymaX	10	SYMAX	SYMAX5C							NRF24L01
Traxxas	43	Traxxas								NRF24L01
V2x2	5	V2x2	JXD506							NRF24L01
V761	48	V761								NRF24L01
V911S	46	V911S*								NRF24L01
WFly	40	WFLY								CYRF6936
WK2x01	30	WK2801	WK2401	W6_5_1	W6_6_1	W6_HEL	W6_HEL_I			CYRF6936
YD717	8	YD717	SKYWLKR	SYMAX4	XINXUN	NIHUI				NRF24L01

• "*" Sub Protocols designated by * suffix will use the NRF24L01 module by default to emulate the XN297L RF chip.
• If a CC2500 module is installed it will be used instead as it is proving to be a better option for the XN297L@250kbps. Each specific sub protocol has a more detailed explanation.

A7105 RF Module

FLYSKY - 1

Extended limits supported

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
A	E	T	R	CH5	CH6	CH7	CH8

Note that the RX ouput will be AETR.

Sub_protocol Flysky - 0

Sub_protocol V9X9 - 1

CH5	CH6	CH7	CH8
FLIP	LIGHT	PICTURE	VIDEO

Sub_protocol V6X6 - 2

CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12
FLIP	LIGHT	PICTURE	VIDEO	HEADLESS	RTH	XCAL	YCAL

Sub_protocol V912 - 3

CH5	CH6
BTMBTN	TOPBTN

Sub_protocol CX20 - 4

Model: Cheerson Cx-20

CH5	CH6	CH7

FLYSKY AFHDS2A - 28

Extended limits and failsafe supported

Telemetry enabled protocol:

• by defaut using FrSky Hub protocol (for example er9x): RX(A1), battery voltage FS-CVT01(A2) and RX&TX RSSI
• if using ersky9x and OpenTX: full telemetry information available

Option is used to change the servo refresh rate. A value of 0 gives 50Hz (min), 70 gives 400Hz (max). Specific refresh rate value can be calculated like this option=(refresh_rate-50)/5.

RX_Num is used to give a number a given RX. You must use a different RX_Num per RX. A maximum of 16 AFHDS2A RXs are supported.

OpenTX suggested RSSI alarm threshold settings (Telemetry tab): Low=15, Critical=12.

If telemetry is incomplete (missing RX RSSI for example), it means that you have to upgrade your RX firmware to version 1.6 or later. You can do it from an original Flysky TX or using a STLink like explained in this tutorial.

AFHDS2A_LQI_CH is a feature which is disabled by defaut in the _config.h file. When enabled, it makes LQI (Link Quality Indicator) available on one of the RX ouput channel (5-14).

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13	CH14
A	E	T	R	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13	CH14

Note that the RX ouput will be AETR whatever the input channel order is.

Sub_protocol PWM_IBUS - 0

Sub_protocol PPM_IBUS - 1

Sub_protocol PWM_SBUS - 2

Sub_protocol PPM_SBUS - 3

HUBSAN - 2

Telemetry enabled for battery voltage and TX RSSI

Option=vTX frequency (H107D) 5645 - 5900 MHz

Sub_protocol H107 - 0

Autobind protocol

Models: Hubsan H102D, H107/L/C/D and H107P/C+/D+

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
A	E	T	R	FLIP	LIGHT	PICTURE	VIDEO	HEADLESS

Sub_protocol H301 - 1

Models: Hubsan H301

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
A	E	T	R	RTH	LIGHT	STAB	VIDEO

Sub_protocol H501 - 2

Models: Hubsan H501S, H122D, H123D

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13
A	E	T	R	RTH	LIGHT	PICTURE	VIDEO	HEADLESS	GPS_HOLD	ALT_HOLD	FLIP	FMODES

H122D: FLIP

H123D: FMODES -> -100%=Sport mode 1,0%=Sport mode 2,+100%=Acro

BUGS - 41

Models: MJX Bugs 3, 6 and 8

Telemetry enabled for RX & TX RSSI, Battery voltage good/bad

RX_Num is used to give a number to a given model. You must use a different RX_Num per MJX Bugs. A maximum of 16 Bugs are supported.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10
A	E	T	R	ARM	ANGLE	FLIP	PICTURE	VIDEO	LED

ANGLE: angle is +100%, acro is -100%

---

CC2500 RF Module

CORONA - 37

Models: Corona 2.4GHz FSS and DSSS receivers.

Extended limits supported

Option for this protocol corresponds to fine frequency tuning. This value is different for each Module and must be accurate otherwise the link will not be stable. Check the Frequency Tuning page to determine it.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8

Sub_protocol COR_V1 - 0

Corona FSS V1 RXs

Sub_protocol COR_V2 - 1

Corona DSSS V2 RXs: CR8D, CR6D and CR4D

To bind V2 RXs you must follow the below procedure (original):

• press the bind button and power on the RX
• launch a bind from Multi -> the RX will blink 2 times
• turn off the RX and TX(=Multi)
• turn on the RX first
• turn on the TX(=Multi) second
• wait for the bind to complete -> the RX will flash, stop and finally fix
• wait some time (more than 30 sec) before turning off the RX
• turn off/on the RX and test that it can reconnect instantly, if not repeat the bind procedure

Sub_protocol FD_V3 - 2

FlyDream RXs like IS-4R and IS-4R0

FRSKYV - 25

Models: FrSky receivers V8R4, V8R7 and V8FR.

• FrSkyV = FrSky 1 way

Extended limits supported

Option for this protocol corresponds to fine frequency tuning. This value is different for each Module and must be accurate otherwise the link will not be stable. Check the Frequency Tuning page to determine it.

CH1	CH2	CH3	CH4
CH1	CH2	CH3	CH4

FRSKYD - 3

Models: FrSky receivers D4R and D8R. DIY RX-F801 and RX-F802 receivers. Also known as D8.

Extended limits supported

Telemetry enabled for A0, A1, RSSI, TSSI and Hub

Option for this protocol corresponds to fine frequency tuning. This value is different for each Module and must be accurate otherwise the link will not be stable. Check the Frequency Tuning page to determine it.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8

FRSKYX - 15

Models: FrSky receivers X4R, X6R and X8R. Also known as D16.

Extended limits and failsafe supported

Telemetry enabled for A1 (RxBatt), A2, RSSI, TSSI and Hub

Option for this protocol corresponds to fine frequency tuning. This value is different for each Module and must be accurate otherwise the link will not be stable. Check the Frequency Tuning page to determine it.

Sub_protocol CH_16 - 0

FCC protocol 16 channels @18ms.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13	CH14	CH15	CH16
CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13	CH14	CH15	CH16

Sub_protocol CH_8 - 1

FCC protocol 8 channels @9ms.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8

Sub_protocol EU_16 - 2

EU-LBT protocol 16 channels @18ms. Note that the LBT part is not implemented, the TX transmits right away.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13	CH14	CH15	CH16
CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13	CH14	CH15	CH16

Sub_protocol EU_8 - 3

EU-LBT protocol 8 channels @9ms. Note that the LBT part is not implemented, the TX transmits right away.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8

HITEC - 39

Models: OPTIMA, MINIMA and MICRO receivers.

Extended limits supported

Option for this protocol corresponds to fine frequency tuning. This value is different for each Module and must be accurate otherwise the link will not be stable. Check the Frequency Tuning page to determine it.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9

Sub_protocol OPT_FW - 0

OPTIMA RXs

Full telemetry available on ersky9x and OpenTX. This is still a WIP.

The TX must be close to the RX for the bind negotiation to complete successfully

Sub_protocol OPT_HUB - 1

OPTIMA RXs

Basic telemetry using FrSky Hub on er9x, ersky9x, OpenTX and any radio with FrSky telemetry support with RX voltage, VOLT2 voltage, TX RSSI and TX LQI.

The TX must be close to the RX for the bind negotiation to complete successfully

Sub_protocol MINIMA - 2

MINIMA, MICRO and RED receivers

SFHSS - 21

Models: Futaba RXs and XK models.

Extended limits and failsafe supported

Option for this protocol corresponds to fine frequency tuning. This value is different for each Module and must be accurate otherwise the link will not be stable. Check the Frequency Tuning page to determine it.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
A	E	T	R	CH5	CH6	CH7	CH8

---

CYRF6936 RF Module

DEVO - 7

Extended limits and failsafe supported

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
A	E	T	R	CH5	CH6	CH7	CH8

Note that the RX ouput will be EATR.

Bind procedure using serial:

• With the TX off, put the binding plug in and power on the RX (RX LED slow blink), then power it down and remove the binding plug. Receiver should now be in autobind mode.
• Turn on the TX, set protocol = Devo with option=0, turn off the TX (TX is now in autobind mode).
• Turn on RX (RX LED fast blink).
• Turn on TX (RX LED solid, TX LED fast blink).
• Wait for bind on the TX to complete (TX LED solid).
• Make sure to set a uniq RX_Num value for model match.
• Change option to 1 to use the global ID.
• Do not touch option/RX_Num anymore.

Bind procedure using PPM:

• With the TX off, put the binding plug in and power on the RX (RX LED slow blink), then power it down and remove the binding plug. Receiver should now be in autobind mode.
• Turn on RX (RX LED fast blink).
• Turn the dial to the model number running protocol DEVO on the module.
• Press the bind button and turn on the TX. TX is now in autobind mode.
• Release bind button after 1 second: RX LED solid, TX LED fast blink.
• Wait for bind on the TX to complete (TX LED solid).
• Press the bind button for 1 second. TX/RX is now in fixed ID mode.
• To verify that the TX is in fixed mode: power cycle the TX, the module LED should be solid ON (no blink).
• Note: Autobind/fixed ID mode is linked to the RX_Num number. Which means that you can have multiple dial numbers set to the same protocol DEVO with different RX_Num and have different bind modes at the same time. It enables PPM users to get model match under DEVO.

Sub_protocol 8CH - 0

Sub_protocol 10CH - 1

Sub_protocol 12CH - 2

Sub_protocol 6CH - 3

Sub_protocol 7CH - 4

WK2X01 - 30

Extended limits supported Autobind protocol

Note: RX ouput will always be AETR independently of the input AETR, RETA...

Sub_protocol WK2801 - 0

Failsafe supported.

This roughly corresponds to the number of channels supported, but many of the newer 6-channel receivers actually support the WK2801 protocol. It is recommended to try the WK2801 protocol 1st when working with older Walkera models before attempting the WK2601 or WK2401 mode, as the WK2801 is a superior protocol. The WK2801 protocol supports up to 8 channels.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
A	E	T	R	CH5	CH6	CH7	CH8

Bind procedure using serial:

• With the TX off, put the binding plug in and power on the RX (RX LED slow blink), then power it down and remove the binding plug. Receiver should now be in autobind mode.
• Turn on the TX, set protocol = WK2X01, sub_protocol = WK2801 with option=0, turn off the TX (TX is now in autobind mode).
• Turn on RX (RX LED fast blink).
• Turn on TX (RX LED solid, TX LED fast blink).
• Wait for bind on the TX to complete (TX LED solid).
• Make sure to set a uniq RX_Num value for model match.
• Change option to 1 to use the global ID.
• Do not touch option/RX_Num anymore.

Bind procedure using PPM:

• With the TX off, put the binding plug in and power on the RX (RX LED slow blink), then power it down and remove the binding plug. Receiver should now be in autobind mode.
• Turn on RX (RX LED fast blink).
• Turn the dial to the model number running protocol protocol WK2X01 and sub_protocol WK2801 on the module.
• Press the bind button and turn on the TX. TX is now in autobind mode.
• Release bind button after 1 second: RX LED solid, TX LED fast blink.
• Wait for bind on the TX to complete (TX LED solid).
• Press the bind button for 1 second. TX/RX is now in fixed ID mode.
• To verify that the TX is in fixed mode: power cycle the TX, the module LED should be solid ON (no blink).
• Note: Autobind/fixed ID mode is linked to the RX_Num number. Which means that you can have multiple dial numbers set to the same protocol DEVO with different RX_Num and have different bind modes at the same time. It enables PPM users to get model match under DEVO.

Sub_protocol WK2401 - 1

The WK2401 protocol is used to control older Walkera models.

CH1	CH2	CH3	CH4
A	E	T	R

Sub_protocol W6_5_1 - 2

WK2601 5+1: AIL, ELE, THR, RUD, GYRO (ch 7) are proportional. Gear (ch 5) is binary. Ch 6 is disabled

CH1	CH2	CH3	CH4	CH5	CH6	CH7
A	E	T	R	GEAR	DIS	GYRO

Sub_protocol W6_6_1 - 3

WK2601 6+1: AIL, ELE, THR, RUD, COL (ch 6), GYRO (ch 7) are proportional. Gear (ch 5) is binary. This mode is highly experimental.

CH1	CH2	CH3	CH4	CH5	CH6	CH7
A	E	T	R	GEAR	COL	GYRO

Sub_protocol W6_HEL - 4 and W6HEL_I - 5

WK2601 Heli: AIL, ELE, THR, RUD, GYRO are proportional. Gear (ch 5) is binary. COL (ch 6) is linked to Thr. If Ch6 >= 0, the receiver will apply a 3D curve to the Thr. If Ch6 < 0, the receiver will apply normal curves to the Thr. The value of Ch6 defines the ratio of COL to THR.

W6HEL_I: Invert COL servo

option= maximum range of COL servo

CH1	CH2	CH3	CH4	CH5	CH6	CH7
A	E	T	R	GEAR	COL	GYRO

DSM - 6

Extended limits supported

Telemetry enabled for TSSI and plugins

option=number of channels from 4 to 12. An invalid option value will end up with 6 channels.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	----	----	CH15
A	E	T	R	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	----	----	TH_KILL

Notes:

• model/type/number of channels indicated on the RX can be different from what the RX is in fact wanting to see. So don't hesitate to test different combinations until you have something working. Using Auto is the best way to find these settings.
• RX output will match the Spektrum standard TAER independently of the input configuration AETR, RETA...
• RX output will match the Spektrum standard throw (1500µs +/- 400µs -> 1100..1900µs) for a 100% input. This is true for both Serial and PPM input. For PPM, make sure the end points PPM_MIN_100 and PPM_MAX_100 in _config.h are matching your TX ouput. The maximum ouput is 1000..2000µs based on an input of 125%.
  • If you want to override the above and get maximum throw (old way) uncomment in _config.h the line #define DSM_MAX_THROW . In this mode to achieve standard throw use a channel weight of 84%.
• TH_KILL is a feature which is enabled on channel 15 by default (can be disabled/changed) in the _config.h file. Some models (X-Vert, Blade 230S...) require a special position to instant stop the motor(s). If the channel 15 is above -50% the throttle is untouched but if it is between -50% and -100%, the throttle output will be forced between -100% and -150%. For example, a value of -80% applied on channel 15 will instantly kill the motors on the X-Vert.

Sub_protocol DSM2_22 - 0

DSM2, Resolution 1024, refresh rate 22ms

Sub_protocol DSM2_11 - 1

DSM2, Resolution 2048, refresh rate 11ms

Sub_protocol DSMX_22 - 2

DSMX, Resolution 2048, refresh rate 22ms

Sub_protocol DSMX_11 - 3

DSMX, Resolution 2048, refresh rate 11ms

Sub_protocol AUTO - 4

The "AUTO" feature enables the TX to automatically choose what are the best settings for your DSM RX and update your model protocol settings accordingly.

The current radio firmware which are able to use the "AUTO" feature are ersky9x (9XR Pro, 9Xtreme, Taranis, ...), er9x for M128(9XR)&M2561 and OpenTX (mostly Taranis). For these firmwares, you must have a telemetry enabled TX and you have to make sure you set the Telemetry "Usr proto" to "DSMx". Also on er9x you will need to be sure to match the polarity of the telemetry serial (normal or inverted by bitbashing), while on ersky9x you can set "Invert COM1" accordinlgy.

J6Pro - 22

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12
A	E	T	R	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12

WFLY - 40

Receivers: WFR04S, WFR07S, WFR09S

Extended limits supported

option=number of channels from 4 to 9. An invalid option value will end up sending 9 channels.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9

---

NRF24L01 RF Module

ASSAN - 24

Extended limits supported

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8

The transmitter must be close to the receiver while binding.

BAYANG - 14

Autobind protocol

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	-	-	CH14	CH15
A	E	T	R	FLIP	RTH	PICTURE	VIDEO	HEADLESS	INVERTED	RATES	-	-	ANAAUX1	ANAAUX2

RATES: -100%(default)=>higher rates by enabling dynamic trims (except for Headless), 100%=>disable dynamic trims

Channels 14 and 15 (ANAAUX1 and ANAAUX2) only available with analog aux channel option, indicated below.

Sub_protocol BAYANG - 0

Models: Eachine H8(C) mini, BayangToys X6/X7/X9, JJRC JJ850, Floureon H101 ...

Option=0 -> normal Bayang protocol

Option=1 -> enable telemetry with Silverxxx firmware. Value returned to the TX using FrSkyD Hub are RX RSSI, TX RSSI, A1=uncompensated battery voltage, A2=compensated battery voltage

Option=2 -> enable analog aux channels with NFE Silverware firmware. Two otherwise static bytes in the protocol overridden to add two 'analog' (non-binary) auxiliary channels.

Option=3 -> both Silverware telemetry and analog aux channels enabled.

Sub_protocol H8S3D - 1

Model: H8S 3D

Same channels assignment as above.

Sub_protocol X16_AH - 2

Model: X16 AH

CH12
TAKE_OFF

Sub_protocol IRDRONE - 3

Model: IRDRONE

CH12	CH13
TAKE_OFF	EMG_STOP

Sub_protocol DHD_D4 - 4

Model: DHD D4

CH12	CH13
TAKE_OFF	EMG_STOP

BUGSMINI - 42

Models: MJX Bugs 3 Mini and 3H

Telemetry enabled for RX RSSI, Battery voltage good/warning/bad

RX_Num is used to give a number to a given model. You must use a different RX_Num per MJX Bugs Mini. A maximum of 16 Bugs Mini are supported.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10
A	E	T	R	ARM	ANGLE	FLIP	PICTURE	VIDEO	LED

ANGLE: angle is +100%, acro is -100%

Sub_protocol BUGSMINI - 0

Sub_protocol BUGS3H - 1

CH11
ALTHOLD

Cabell - 34

Homegrown protocol with variable number of channels (4-16) and telemetry (RSSI, V1, V2).

It is a FHSS protocol developed by Dennis Cabell (KE8FZX) using the NRF24L01+ 2.4 GHz transceiver. 45 channels are used frequency hop from 2.403 through 2.447 GHz. The reason for using 45 channels is to keep operation within the overlap area between the 2.4 GHz ISM band (governed in the USA by FCC part 15) and the HAM portion of the band (governed in the USA by FCC part 97). This allows part 15 compliant use of the protocol, while allowing licensed amateur radio operators to operate under the less restrictive part 97 rules if desired.

Additional details about configuring and using the protocol are available at the RX project at: https://github.com/soligen2010/RC_RX_CABELL_V3_FHSS

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13	CH14	CH15	CH16
A	E	T	R	AUX1	AUX2	AUX3	AUX4	AUX5	AUX6	AUX7	AUX8	AUX9	AUX10	AUX11	AUX12

Sub_protocol CABELL_V3 - 0

4 to 16 channels without telemetry

Sub_protocol CABELL_V3_TELEMETRY - 1

4 to 16 channels with telemetry (RSSI, V1, V2). V1 & V2 can be used to return any analog voltage between 0 and 5 volts, so can be used for battery voltage or any other sensor that provides an analog voltage.

Sub_protocol CABELL_SET_FAIL_SAFE - 6

Stores failsafe values in the RX. The channel values are set when the sub-protocol is changed to 6, so hold sticks in place as the sub-protocol is changed.

Sub_protocol CABELL_UNBIND - 7

The receiver bound to the model is un-bound. This happens immediately when the sub-protocol is set to 7.

CG023 - 13

Autobind protocol

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
A	E	T	R	FLIP	LIGHT	PICTURE	VIDEO	HEADLESS

Sub_protocol CG023 - 0

Models: EAchine CG023/CG031/3D X4

Sub_protocol YD829 - 1

Models: Attop YD-822/YD-829/YD-829C ...

CH5	CH6	CH7	CH8	CH9
FLIP		PICTURE	VIDEO	HEADLESS

CX10 - 12

Autobind protocol

CH1	CH2	CH3	CH4	CH5	CH6
A	E	T	R	FLIP	RATE

Rate: -100%=rate 1, 0%=rate 2, +100%=rate 3

Sub_protocol GREEN - 0

Models: Cheerson CX-10 green pcb

Same channels assignement as above.

Sub_protocol BLUE - 1

Models: Cheerson CX-10 blue pcb & some newer red pcb, CX-10A, CX-10C, CX11, CX12, Floureon FX10, JJRC DHD D1

CH5	CH6	CH7	CH8
FLIP	RATE	PICTURE	VIDEO

Rate: -100%=rate 1, 0%=rate 2, +100%=rate 3 or headless for CX-10A

Sub_protocol DM007 - 2

CH5	CH6	CH7	CH8	CH9
FLIP	MODE	PICTURE	VIDEO	HEADLESS

Sub_protocol JC3015_1 - 4

CH5	CH6	CH7	CH8
FLIP	MODE	PICTURE	VIDEO

Sub_protocol JC3015_2 - 5

CH5	CH6	CH7	CH8
FLIP	MODE	LED	DFLIP

Sub_protocol MK33041 - 6

CH5	CH6	CH7	CH8	CH9	CH10
FLIP	MODE	PICTURE	VIDEO	HEADLESS	RTH

DM002 - 33

Autobind protocol

Only 3 TX IDs available, change RX_Num value 0-1-2 to cycle through them

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11
A	E	T	R	FLIP	LED	CAMERA1	CAMERA2	HEADLESS	RTH	RATE_LOW

E01X - 45

Autobind protocol

Sub_protocol E012 - 0

Models: Eachine E012

This protocol has been reported to not work properly due to the emulation of the HS6200 RF component using the NRF24L01. The option value is used to adjust the timing, try every values between -127 and +127. If it works please report which value you've used.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
A	E	T	R		FLIP		HEADLESS	RTH

Sub_protocol E015 - 1

Models: Eachine E015

This protocol has been reported to not work properly due to the emulation of the HS6200 RF component using the NRF24L01. The option value is used to adjust the timing, try every values between -127 and +127. If it works please report which value you've used.

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
A	E	T	R	ARM	FLIP	LED	HEADLESS	RTH

Sub_protocol E016H - 2

Models: Eachine E016H

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
A	E	T	R	STOP	FLIP	-	HEADLESS	RTH

ESKY - 16

CH1	CH2	CH3	CH4	CH5	CH6
A	E	T	R	GYRO	PITCH

ESKY150 - 35

ESky protocol for small models since 2014 (150, 300, 150X, ...)

Number of channels are set with option. option=0 4 channels and option=1 7 channels. An invalid option value will end up with 4 channels.

CH1	CH2	CH3	CH4	CH5	CH6	CH7
A	E	T	R	FMODE	AUX6	AUX7

FMODE and AUX7 have 4 positions: -100%..-50%=>0, -50%..5%=>1, 5%..50%=>2, 50%..100%=>3

FY326 - 20

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
A	E	T	R	FLIP	RTH	HEADLESS	EXPERT	CALIBRATE

FQ777 - 23

Model: FQ777-124 (with SV7241A)

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
A	E	T	R	FLIP	RTH	HEADLESS	EXPERT

GD00X - 47

Model: GD005 C-17 Transport, GD006 DA62 and ZC-Z50

If the model does not respond well to inputs or hard to bind, you can try to set Power to Low. But this protocol is known to be problematic because it's using the xn297L emulation with a transmission speed of 250kbps therefore it doesn't work very well with every modules, this is an hardware issue with the accuracy of the components used and nothing we can do about it in the firmware.

If a CC2500 rf component is available it will be used in place of the NRF24L01 which might fix the issue mentioned above. Option is used for fine frequency tuning like any CC2500 protocols. Check the Frequency Tuning page to determine it if necessary.

CH1	CH2	CH3	CH4	CH5	CH6	CH7
A		T		TRIM	LED	RATE

TRIM: either use this channel for trim only or add a mixer with aileron to increase the roll rate.

RATE: -100% high rate, +100% low rate

Sub_protocol GD_V1 - 0

First generation of GD models, ZC-Z50

Sub_protocol GD_V2 - 1

New generation of GD models

GW008 - 32

Model: Global Drone GW008 from Banggood

There are 3 versions of this small quad, this protocol is for the one with a XNS104 IC in the stock Tx and PAN159CY IC in the quad. The xn297 version is compatible with the CX10 protocol (green pcb). The LT8910 version is not supported yet.

CH1	CH2	CH3	CH4	CH5
A	E	T	R	FLIP

H8_3D - 36

Autobind protocol

Sub_protocol H8_3D - 0

Models: EAchine H8 mini 3D, JJRC H20/H22/H11D

CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13
FLIP	LIGTH	PICTURE	VIDEO	OPT1	OPT2	CAL1	CAL2	GIMBAL

JJRC H20: OPT1=Headless, OPT2=RTH

JJRC H22: OPT1=RTH, OPT2=180/360° flip mode

H8 3D: OPT1=RTH then press a direction to enter headless mode (like stock TX), OPT2=switch 180/360° flip mode

CAL1: H8 3D acc calib, H20/H20H headless calib CAL2: H11D/H20/H20H acc calib

Sub_protocol H20H - 1

CH6=Motors on/off

Sub_protocol H20 Mini - 2

Only 3 TX IDs available, change RX_Num value 0-1-2 to cycle through them

Sub_protocol H30 Mini - 3

Only 4 TX IDs available, change RX_Num value 0-1-2_3 to cycle through them

HISKY - 4

Sub_protocol Hisky - 0

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
A	E	T	R	GEAR	PITCH	GYRO	CH8

GYRO: -100%=6G, +100%=3G

Sub_protocol HK310 - 1

Models: RX HK-3000, HK3100 and XY3000 (TX are HK-300, HK-310 and TL-3C)

Failsafe supported

CH1	CH2	CH3	CH4	CH5
		T	R	AUX

KN - 9

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11
A	E	T	R	DR	THOLD	IDLEUP	GYRO	Ttrim	Atrim	Etrim

Dual Rate: +100%=full range, Throttle Hold: +100%=hold, Idle Up: +100%=3D, GYRO: -100%=6G, +100%=3G

Sub_protocol WLTOYS - 0

Sub_protocol FEILUN - 1

Same channels assignement as above.

HONTAI - 26

Autobind protocol

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11
A	E	T	R	FLIP	LED	PICTURE	VIDEO	HEADLESS	RTH	CAL

Sub_protocol HONTAI - 0

Sub_protocol JJRCX1 - 1

CH6
ARM

Sub_protocol X5C1 clone - 2

Sub_protocol FQ777_951 - 3

KF606 - 49

Model: KF606

If the model does not respond well to inputs or hard to bind, you can try to set Power to Low. But this protocol is known to be problematic because it's using the xn297L emulation with a transmission speed of 250kbps therefore it doesn't work very well with every modules, this is an hardware issue with the accuracy of the components used and nothing we can do about it in the firmware.

If a CC2500 rf component is available it will be used in place of the NRF24L01 which might fix the issue mentioned above. Option is used for fine frequency tuning like any CC2500 protocols. Check the Frequency Tuning page to determine it if necessary.

CH1	CH2	CH3	CH4	CH5
A		T		TRIM

MJXQ - 18

Autobind protocol

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13	CH14
A	E	T	R	FLIP	LED	PICTURE	VIDEO	HEADLESS	RTH	AUTOFLIP	PAN	TILT	RATE

RATE: -100%(default)=>higher rates by enabling dynamic trims (except for Headless), 100%=>disable dynamic trims

Sub_protocol WLH08 - 0

Sub_protocol X600 - 1

Only 3 TX IDs available, change RX_Num value 0..2 to cycle through them

Sub_protocol X800 - 2

Only 3 TX IDs available, change RX_Num value 0..2 to cycle through them

Sub_protocol H26D - 3

Only 3 TX IDs available, change RX_Num value 0..2 to cycle through them

Sub_protocol E010 - 4

15 TX IDs available, change RX_Num value 0..14 to cycle through them

If the model does not respond well to inputs or hard to bind, you can try to set Power to Low. But this protocol is known to be problematic because it's using the xn297L emulation with a transmission speed of 250kbps therefore it doesn't work very well with every modules, this is an hardware issue with the accuracy of the components used and nothing we can do about it in the firmware.

If a CC2500 rf component is available it will be used in place of the NRF24L01 which might fix the issue mentioned above. Option is used for fine frequency tuning like any CC2500 protocols. Check the Frequency Tuning page to determine it if necessary.

Sub_protocol H26WH - 5

CH6
ARM

Only 1 TX ID available

Sub_protocol PHOENIX - 6

CH6
ARM

MT99XX - 17

Autobind protocol

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
A	E	T	R	FLIP	LED	PICTURE	VIDEO	HEADLESS

Sub_protocol MT99 - 0

Models: MT99xx

Sub_protocol H7 - 1

Models: Eachine H7, Cheerson CX023

Sub_protocol YZ - 2

Model: Yi Zhan i6S

Only one model can be flown at the same time since the ID is hardcoded.

If the model does not respond well to inputs or hard to bind, you can try to set Power to Low. But this protocol is known to be problematic because it's using the xn297L emulation with a transmission speed of 250kbps therefore it doesn't work very well with every modules, this is an hardware issue with the accuracy of the components used and nothing we can do about it in the firmware.

Sub_protocol LS - 3

Models: LS114, 124, 215

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
A	E	T	R	FLIP	INVERT	PICTURE	VIDEO	HEADLESS

Sub_protocol FY805 - 4

Model: FY805

Only 1 ID available

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
A	E	T	R	FLIP				HEADLESS

NCC1701 - 44

Model: Air Hogs Star Trek USS Enterprise NCC-1701-A

Autobind protocol

Telemetry: RSSI is a dummy value. A1 voltage is dummy but used for crash detection. In case of a crash event A1>0V, you can assign a sound to be played on the TX in that case (siren on the original transmitter).

Only 9 IDs available, cycle through them using RX_Num.

CH1	CH2	CH3	CH4	CH5
A	E	T	R	Warp

Potensic - 51

Models: Potensic A20

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
A	E	T	R	TAKE_OFF/LANDING	EMERGENCY	MODE	HEADLESS

TAKE_OFF/LANDING: momentary switch -100% -> +100%

EMERGENCY: Stop +100%

MODE: Beginner -100%, Medium 0%, Advanced +100%

HEADLESS: Off -100%, On +100%

Q2X2 - 29

Sub_protocol Q222 - 0

Models: Q222 v1 and V686 v2

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12
A	E	T	R	FLIP	LED	MODULE2	MODULE1	HEADLESS	RTH	XCAL	YCAL

Sub_protocol Q242 - 1 and Q282 - 2

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12
A	E	T	R	FLIP	LED	PICTURE	VIDEO	HEADLESS	RTH	XCAL	YCAL

Model: JXD 509 is using Q282 with CH12=Start/Stop motors

Q303 - 31

Autobind protocol

CH1	CH2	CH3	CH4
A	E	T	R

Sub_protocol Q303 - 0

If the model does not respond well to inputs or hard to bind, you can try to set Power to Low. But this protocol is known to be problematic because it's using the xn297L emulation with a transmission speed of 250kbps therefore it doesn't work very well with every modules, this is an hardware issue with the accuracy of the components used and nothing we can do about it in the firmware.

CH5	CH6	CH7	CH8	CH9	CH10	CH11
AHOLD	FLIP	PICTURE	VIDEO	HEADLESS	RTH	GIMBAL

GIMBAL needs 3 position -100%/0%/100%

Sub_protocol CX35 - 1

CH5	CH6	CH7	CH8	CH9	CH10	CH11
ARM	VTX	PICTURE	VIDEO		RTH	GIMBAL

ARM is 2 positions: land / take off

Each toggle of VTX will increment the channel.

Gimbal is full range.

Sub_protocol CX10D - 2 and Sub_protocol CX10WD - 3

CH5	CH6
ARM	FLIP

ARM is 3 positions: -100%=land / 0%=manual / +100%=take off

Redpine - 50

Link to the forum

Sub_protocol FAST - 0

Sub_protocol SLOW - 1

Shenqi - 19

Autobind protocol

Model: Shenqiwei 1/20 Mini Motorcycle

CH1	CH2	CH3	CH4
	T	R

Throttle +100%=full forward,0%=stop,-100%=full backward.

SLT - 11

Autobind protocol

Sub_protocol V1 - 0

CH1	CH2	CH3	CH4	CH5	CH6
A	E	T	R	GEAR	PITCH

Sub_protocol V2 - 1

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8
A	E	T	R	CH5	CH6	CH7	CH8

Sub_protocol Q100 - 2

Models: Dromida Ominus UAV

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13
A	E	T	R	RATES	-	CH7	CH8	MODE	FLIP	-	-	CALIB

RATES takes any value between -50..+50%: -50%=min rates, 0%=mid rates (stock setting), +50%=max rates

CH7 and CH8 have no visible effect

MODE: -100% level, +100% acro

FLIP: sets model into flip mode for approx 5 seconds at each throw of switch (rear red LED goes out while active) -100%..+100% or +100%..-100%

CALIB: -100% normal mode, +100% gyro calibration

Sub_protocol Q200 - 3

Model: Dromida Ominus Quadcopter FPV, the Nine Eagles - FENG FPV and may be others

Dromida Ominus FPV channels mapping:

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13
A	E	T	R	RATES	-	CH7	CH8	MODE	FLIP	VID_ON	VID_OFF	CALIB

FENG FPV: channels mapping:

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12	CH13
A	E	T	R	RATES	-	CH7	CH8	FLIP	MODE	VID_ON	VID_OFF	CALIB

RATES takes any value between -50..+50%: -50%=min rates, 0%=mid rates (stock setting), +50%=max rates

CH7 and CH8 have no visible effect

MODE: -100% level, +100% acro

FLIP: sets model into flip mode for approx 5 seconds at each throw of switch (rear red LED goes out while active) -100%..+100% or +100%..-100%

CALIB: -100% normal mode, +100% gyro calibration

Sub_protocol MR100 - 4

Models: Vista UAV, FPV, FPV v2

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11	CH12
A	E	T	R	RATES	-	CH7	CH8	MODE	FLIP	VIDEO	PICTURE

RATES takes any value between -50..+50%: -50%=min rates, 0%=mid rates (stock setting), +50%=max rates

CH7 and CH8 have no visible effect

FLIP: sets model into flip mode for approx 5 seconds at each throw of switch (rear red LED goes out while active) -100%..+100% or +100%..-100%

MODE: -100% level, +100% acro

Symax - 10

Autobind protocol

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
A	E	T	R	FLIP	RATES	PICTURE	VIDEO	HEADLESS

RATES: -100%(default)=>disable dynamic trims, +100%=> higher rates by enabling dynamic trims (except for Headless)

Sub_protocol SYMAX - 0

Models: Syma X5C-1/X11/X11C/X12

Sub_protocol SYMAX5C - 1

Model: Syma X5C (original) and X2

V2X2 - 5

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9	CH10	CH11
A	E	T	R	FLIP	LIGHT	PICTURE	VIDEO	HEADLESS	MAG_CAL_X	MAG_CAL_Y

Sub_protocol V2x2 - 0

Models: WLToys V202/252/272, JXD 385/388, JJRC H6C, Yizhan Tarantula X6 ...

PICTURE: also automatic Missile Launcher and Hoist in one direction

VIDEO: also Sprayer, Bubbler, Missile Launcher(1), and Hoist in the other dir

Sub_protocol JXD506 - 1

Model: JXD 506

CH10	CH11	CH12
Start/Stop	EMERGENCY	CAMERA_UP/DN

V761 - 48

Model: Volantex V761 and may be other

Warning: Only 3 IDs, you can cycle through them using RX_Num.

CH1	CH2	CH3	CH4	CH5
-	E	T	R	GYRO

Gyro: -100%=Beginer mode (Gyro on, yaw and pitch rate limited), 0%=Mid Mode ( Gyro on no rate limits), +100%=Mode Expert Gyro off

V911S - 46

Models: WLtoys V911S, XK A110

If the model does not respond well to inputs or hard to bind, you can try to set Power to Low. But this protocol is known to be problematic because it's using the xn297L emulation with a transmission speed of 250kbps therefore it doesn't work very well with every modules, this is an hardware issue with the accuracy of the components used and nothing we can do about it in the firmware.

If a CC2500 rf component is available it will be used in place of the NRF24L01 which might fix the issue mentioned above. Option is used for fine frequency tuning like any CC2500 protocols. Check the Frequency Tuning page to determine it if necessary.

CH1	CH2	CH3	CH4	CH5
A	E	T	R	CALIB

YD717 - 8

Autobind protocol

CH1	CH2	CH3	CH4	CH5	CH6	CH7	CH8	CH9
A	E	T	R	FLIP	LIGHT	PICTURE	VIDEO	HEADLESS

Sub_protocol YD717 - 0

Sub_protocol SKYWLKR - 1

Sub_protocol SYMAX4 - 2

Sub_protocol XINXUN - 3

Sub_protocol NIHUI - 4

Same channels assignement as above.

OpenLRS module

OpenLRS - 27

This is a reservation for OpenLRSng which is using Multi's serial protocol for their modules: https://openlrsng.org/. On the Multi side there is no protocol affected on 27 so it's just ignored.