This is RS485 version of a simple RF24 node on Atmega328

D7 pin used for control RS485 DE/RE input.

On long side of board present 11-pin header include:

• D2, D3, D4, D5
• A0, A1, A4/SDA, A5/SCL
• GND, 5V

On short side of board present two pin header include:

• 5V, GND, D2, D3 (for simple connect sensors like DS18B20, DHT22)
• RES, TX, RX (for connect UART)

On bottom side of board present MISO, MOSI, SCK and CSN for programming bootloader to ATmega328.

Present place to solder pull-up resistors for RES, D2, D3, SDA, SCL signals.
It is also possible to install LED connected between D6 pin and 5V through 510Ohm resistor.

You can order PCB from PCBs.io - 4pcs for $4.65, black 1.6mm PCB

08/07/2019 UPDATE !!! Tested in hardware now !!!

30/09/2019 ATTENTION !!! Possible unstable work node with LP2950CZ-50 LDO !!! (temporary using AMS1117, order HT7550-1 for testing as LDO for power of 12V)

This is my ALARM module base board with installed MYSNodeRS485 module (used to connection PIR sensor of standart secirity system):

This is my LIGHT module with installed MYSNodeRS485 module for lamp connection to MySensors:

Connection of module: