Update README.md

README.md

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 # RS485-UART-EchoTest
-This sketch is useful for debugging and testing RS485/UART wirings.
+
+Version: 1.0
+Date: 2020-12-15
+
+This sketch is useful for debugging and testing RS485/UART wirings. 
+Often the remote device is mounted somewhere on a rooftop or another 
+inconvenient place. That's where this tool comes in and offers you a 
+simulation for your lab.
+
+It was intentionally made for the wind direction sensor:
+https://github.com/AndreasExner/iobroker-IoT-WindSensor
+
+But it can be used for different purposes as well.
+
+
+
+#### Configuration
+
+```c++
+byte windSensorFrame[] = {0x01, 0x03, 0x04, 0x00, 0x5A, 0x00, 0x00, 0x00, 0x00}; // default answer frame for the wind sensor DO NOT CHANGE
+byte customFrame[] = {0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; // your custom answer frame (CRC will be calculated automatically)
+
+bool useWindSensorFrame = true; // echos a random wind direction if true, a custom frame or a copy of the incoming frame if false
+bool useCustomFrame = false; // echos the custom frame if true, a copy of the incoming frame if false 
+```
+
+
+
+#### Tested environment
+
+- Software
+  - Arduino IDE 1.8.13 (Windows)
+  - EspSoftwareSerial 6.10.0 [plerup/espsoftwareserial: Implementation of the Arduino software serial for ESP8266 (github.com)](https://github.com/plerup/espsoftwareserial)
+- Hardware
+  - NodeMCU Lolin V3 (ESP8266MOD 12-F)
+  - NodeMCU D1 Mini (ESP8266MOD 12-F)
+  - 5 V MAX485 / RS485 Modul TTL to RS-485 MCU
+
+
+
+#### Wiring
+