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+| Supported Targets | ESP32 | ESP32-C2 | ESP32-C3 | ESP32-C5 | ESP32-C6 | ESP32-C61 | ESP32-H2 | ESP32-H21 | ESP32-H4 | ESP32-P4 | ESP32-S2 | ESP32-S3 |
+| ----------------- | ----- | -------- | -------- | -------- | -------- | --------- | -------- | --------- | -------- | -------- | -------- | -------- |
+
+# UART RS485 Echo Example
+
+(See the README.md file in the upper level 'examples' directory for more information about examples.)
+
+This is an example which echoes any data it receives on UART port back to the sender in the RS485 network.
+It uses ESP-IDF UART software driver in RS485 half duplex transmission mode and requires external connection of bus drivers.
+The approach demonstrated in this example can be used in user application to transmit/receive data in RS485 networks.
+
+## How to use example
+
+### Hardware Required
+PC + USB Serial adapter connected to USB port + RS485 line drivers + Espressif development board.
+The MAX483 line driver is used for example below but other similar chips can be used as well.
+
+#### RS485 example connection circuit schematic:
+```
+         VCC ---------------+                               +--------------- VCC
+                            |                               |
+                    +-------x-------+               +-------x-------+
+         RXD <------| RO            |               |             RO|-----> RXD
+                    |              B|---------------|B              |
+         TXD ------>| DI  MAX483    |    \  /       |    MAX483   DI|<----- TXD
+ESP32 BOARD         |               |   RS-485 side |               |  SERIAL ADAPTER SIDE
+         RTS --+--->| DE            |    /  \       |             DE|---+
+               |    |              A|---------------|A              |   |
+               +----| /RE           |               |            /RE|---+-- RTS
+                    +-------x-------+               +-------x-------+
+                            |                               |
+                           ---                             ---
+```
+
+#### Connect an external RS485 serial interface to an ESP32 board
+Connect a USB-to-RS485 adapter to a computer, then connect the adapter's A/B output lines with the corresponding A/B output lines of the RS485 line driver connected to the ESP32 chip (see figure above).
+```
+  ------------------------------------------------------------------------------------------------------------------------------
+  |  UART Interface       | #define            | Default pin for ESP32 | Default pins for others   | External RS485 Driver Pin |
+  | ----------------------|--------------------|-----------------------|---------------------------|---------------------------|
+  | Transmit Data (TxD)   | CONFIG_MB_UART_TXD | GPIO23                | GPIO9                     | DI                        |
+  | Receive Data (RxD)    | CONFIG_MB_UART_RXD | GPIO22                | GPIO8                     | RO                        |
+  | Request To Send (RTS) | CONFIG_MB_UART_RTS | GPIO18                | GPIO10                    | ~RE/DE                    |
+  | Ground                | n/a                | GND                   | GND                       | GND                       |
+  ------------------------------------------------------------------------------------------------------------------------------
+```
+Note: Each target chip has different GPIO pins available for UART connection. Please refer to UART documentation for selected target for more information.
+
+### Configure the project
+```
+idf.py menuconfig
+```
+
+### Build and Flash
+Build the project and flash it to the board, then run monitor tool to view serial output:
+```
+idf.py -p PORT flash monitor
+```
+
+(To exit the serial monitor, type ``Ctrl-]``.)
+
+See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.
+
+#### Setup external terminal software
+Refer to the example and set up a serial terminal program to the same settings as of UART in ESP32-WROVER-KIT board.
+Open the external serial interface in the terminal. By default if no any symbols are received, the application sends character `.` to check transmission side.
+When typing message and push send button in the terminal you should see the message `RS485 Received: [ your message ]`, where "your message" is the message you sent from terminal.
+Verify if echo indeed comes from your board by disconnecting either `TxD` or `RxD` pin. Once done there should be no any `.` displayed.
+
+## Example Output
+Example output of the application:
+```
+I (655020) RS485_ECHO_APP: Received 12 bytes:
+[ 0x79 0x6F 0x75 0x72 0x20 0x6D 0x65 0x73 0x73 0x61 0x67 0x65 ]
+```
+The received message is showed in hexadecimal form in the brackets.
+
+## Troubleshooting
+When example software does not show the `.` symbol, the issue is most likely related to connection errors of the external RS485 interface.
+Check the RS485 interface connection with the environment according to schematic above and restart the application.
+Then start terminal software and open the appropriate serial port.
+