elrs-rx-2.4g-pwm

#PrefaceExpressLRS
open source remote control protocol, high performance, long distance, high refresh.
https://github.com/ExpressLRS/ExpressLRS/
 
#Introduction:
This ELRS receiver is a special version of PWM output signal. It supports 5 channels of pwm output. It is suitable for fixed-wing aviation models without flight control. It can also be flashed into ordinary firmware to output crsf. protocol.
It should be noted that the current characteristics of ELRS are that only the first 4 signals are full-scale output, the 5th channel is a two-stage output of 1000 or 2000, and the 8-12 channels can output up to 1024bit signals according to the 2 modes.
 
 
#Features
1. Made using mature domestic RF modules, the receiving signal is stable and reliable. Ebyte E28 2G4M12S, based on Lora SX1280 protocol, 100mw power (return data transmission ≈ 16mw).
2. The 2.4G frequency is legal and available, so there is no need to worry about the risk of 433M and 915M frequencies being checked.
3. The 5-channel PWM signal output is 50Hz, and the 2.54 DuPont connector is directly connected to the fixed-wing ESC and servo;
4. Non-PWM firmware can also be input, and the standard CRSF signal can be output to connect to the flight control. (2 TX and 3 RX, connected to the rx tx of the flight control)
5. Each signal output by the PWM can be customized for mapping, and can be adjusted by opening the 10.0.0.1 page in WiFi mode. (Default 1 2 3 throttle 4 5 unlock two-stage switch)
6. Using ESP8285 chip, it comes with WiFi function, which can be used to update and upgrade firmware and adjust pwm output mapping on WiFi web page.
7. 5v power supply protection against reverse connection, using S4 diodes, voltage drop 0.3V, rated current 350ma*4.7v to meet the maximum power of the receiver (maximum 85ma*3.3v when WiFi flashing)
8. Reserved voltage detection pad 1K :10K to realize voltage return to the remote control. (20220113 is not currently supported, and the 1K 10K resistor of the accessory can be soldered without welding) 9.
Size: 27mm
(However, ESP8285 is in a qfn32 package, so it is still difficult. Use a blade soldering iron to repair the soldering and rosin to help avoid soldering.)
 
#Burning firmware
for the first time
1. A USB serial port tool is required, and the USB ttl of ch340 is recommended.
USB-TTL receiver
    5V 5V
   GND GND
    2 TX RX
    3 RX TX
2. Before connecting the serial port tool to the computer, you need to short-circuit boot to enter the burning mode, that is, short-circuit 1 (boot) and gnd.
3. Use expresslrs configurator ground station to compile and flash, or VS CODE to compile and flash. If you already have the xxxx.bin firmware file, you can also use the NodeMCU software to directly burn it (select DOUT mode)
4. Compile & flash, select the target target: DIY-2400-RX-PWMP (the output crsf protocol is DIY-2400-RX- ESP8285-SX1280)
5. If it prompts success, you can
 
re-flash the firmware later. You can also do the same as above, but it is more convenient to use WiFi to flash. If you have a .bin file, you can also upgrade it on your phone.
WIFI upgrade and update firmware
1. After the receiver is powered on, it flashes slowly for 1 second and is ready to connect. If the remote control is not linked, it will enter the WiFi upgrade mode in 20 to 60 seconds and flash quickly (if it is connected to the remote control, you can force the rx receiver WiFi mode in the wifi option in Lua). )
2. Search the computer or mobile phone to connect ExpressLRS rx name, password expresslrs
3. A. Open the file in the web page http://10.0.0.1, select the .bin file and click 'Upgrade'
or B. Use the ground station or vscode software, in When compiling and flashing, select DIY-2400-RX-PWMP-wifi. This WiFi method will automatically burn and wait for completion.