4 IN 1 RF module integrates four RF chips( CC2500, NRF24L01, A7105, CYRF6936 ) in one single PCB board.
It supports more than 10 different protocols while working with MCU board, such as Frsky, Flysky, Hisky, Devo, DSM2, V2x2 and so on.
You can use arduino nano to DIY your own MCU board, it also can be used with walkera devo transmitter.

Description:

1. Arduino promini 5V/16Mhz(Protocols are using as witness the existing on board LED on B5 pin). It can be used also any setup with Atmega328P/16Mhz.
2. A7105 module(X7105-D03 PA/LNA module, V911,V939 harvested TX modules)
3. CC2500 PA/LNA module
4. Nrf24L01 PA/LNA module
5. Devo module(based on CYRF6936)
6. AMS1117 -5V and AMS1117-3.3V, LDO voltage regulator or any other regulators over 800mA.
7. Resistor 20K(between NRF_CE pin to Vcc)
8. Caps 22-47uF(3 pcs on ldo's)
9. Rotary dip switch 16 positions or DIP switch 4 positions this is required only in PPM mode.
Now in the serial mode with er9x/ersky9x/opentx there is no need to use dial switch anymore.


Pin function:
NumberNamePropertyDescription
1VCCPower3.3V Power supply
2GNDPowerground
3PE1inputSwitch for RF chipsSee the truth table
4PE2inputSwitch for RF chipsSee the truth table
5CSN1inputA7105 chip select
6CSN2inputCC2500 chip select
7CSN3inputNRF24L01 chip select
8CSN4inputCYRF6936 chip select
9SCKinputSPI clock signal
10MOSIinputSPI input for slave device
11MISOoutputSPI output for slave device
12CYRF_RSTinputCYRF6936 Reset
16RFOin/outRF signal, connect to antenna
othersGNDPowerground
 
Truth table:
statusPE1PE2
A7105 RF signal to antennaLow levelLow level
CC2500 RF signal to antennaLow levelhigh level
NRF24L01 RF signal to antennahigh levelLow level
CYRF6936 RF signal to antennahigh levelhigh level

For more information, please visit the RCG forum:
HTTPS://www.rcgroups.com/forums/showthread.php?t=2165676
Supported Protocols:
 - Flysky (Generation I protocol,based on A7105,tested)
- Hubsan (Based on A7105,tested)
- Frsky (Based on CC2500,tested)
- Hisky (Based on24L01,tested)
- V2x2 (Based on 24L01)
- Dsm2 (Based on CYRF6936,tested)
- Devo (Based on CYRF6936,tested)
- YD717 (Based on 24L01 )
- KN (V977,Based on 24L01,tested)
- SymaX (Based on 24L01)
- SLT (Based on 24L01)
- CX10 (Based on 24L01)
- CG-023
- BAYANG
- SIMAX5C

Note: 
The above protocols are transplanted from open source projects based on the remote control Walkera DEVIATION,the the original author have tested almost the protocols,but he is not specially test for this 4 in 1 wireless module,the protocols our supplier tested have been stated above,untested protocols does not rule out is not supported,but there may be a problem of program configuration,so not rule out the subsequent firmware can support.

Open source protocol is mostly cracked,protocol version is constantly updated,inevitably there are omissions. Including but not limited to the following issues:
- Part program version DSM2 have protocol compatibility problems.
- Some receiver (original AR600) need to rebind per use,some receiver (Spektrum integrated receiver) frame rate is a bit slow. This issue basically determine the problem is on the program itself.

Tested Ground Control Distance:
CC2500: V8FR receiver with Frsky protocol,about 240m.
A7105: WLToys V911 helicopter with Flysky 8 ch receiver,based on Flysky protocol,about 240m.
CYFR6936: Spektrum MCPX helicopter with DSM2 protocol,Walkera SUPERCP helicopter with DEVO protocol,about 200m,
NRF24L01: WLToys V977 helicopter with KN protocol,use Walkera DEVO transmitter,about 200m (If equipped with MCU baseplate,only 50m). Hisky HCP100S helicopter with Hisky protocol,about 70m.

Firmware & Software,please Click Here

Example for MCU Board:

Package included:

1 x DIY 2.4G CC2500 NRF24L01 A7105 CYRF6936 Multi RF 4 IN 1 Wireless Module