updated readme

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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 | Linux |
-| ----------------- | ----- | -------- | -------- | -------- | -------- | --------- | -------- | --------- | -------- | -------- | -------- | -------- | ----- |
+# DHT11 Temperature & Humidity Sensor for ESP32-C3

-# Hello World Example
+ESP-IDF project that reads temperature and humidity data from a DHT11 sensor and prints it to the serial console.

-Starts a FreeRTOS task to print "Hello World".
+## Overview

-(See the README.md file in the upper level 'examples' directory for more information about examples.)
+This project reads data from a **DHT11** digital temperature and humidity sensor using the ESP32-C3 microcontroller. It implements the DHT11 communication protocol in software, reads sensor values every 5 seconds, validates the checksum, and displays:

-## How to use example
+- Current date and time (derived from compile time)
+- Chip information (model, cores, features, flash size, silicon revision)
+- Humidity percentage with 1 decimal place
+- Temperature in Celsius with 1 decimal place
+- Checksum validation status

-Follow detailed instructions provided specifically for this example.
+## Hardware Requirements

-Select the instructions depending on Espressif chip installed on your development board:
+| Component | Details |
+|-----------|---------|
+| Microcontroller | ESP32-C3 |
+| Sensor | DHT11 (AM2302) |
+| Connection | Single wire + pull-up resistor |
+| Data Pin | **GPIO 0** (configurable in `main/main.c`) |
+| Resistor | 4.7kΩ - 10kΩ pull-up between VCC and DATA |

- [ESP32 Getting Started Guide](https://docs.espressif.com/projects/esp-idf/en/stable/get-started/index.html)
- [ESP32-S2 Getting Started Guide](https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/get-started/index.html)
-
-
-## Example folder contents
-
-The project **hello_world** contains one source file in C language [hello_world_main.c](main/hello_world_main.c). The file is located in folder [main](main).
-
-ESP-IDF projects are built using CMake. The project build configuration is contained in `CMakeLists.txt` files that provide set of directives and instructions describing the project's source files and targets (executable, library, or both).
-
-Below is short explanation of remaining files in the project folder.
+### Wiring Diagram

 ```
-├── CMakeLists.txt
-├── pytest.py      Python script used for automated testing
-├── main
-│   ├── CMakeLists.txt
-│   └── hello_world_main.c
-└── README.md                  This is the file you are currently reading
+DHT11        ESP32-C3
+  VCC  ------ 3V3
+  DATA ----- GPIO0
+  GND  ------ GND
 ```

-For more information on structure and contents of ESP-IDF projects, please refer to Section [Build System](https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-guides/build-system.html) of the ESP-IDF Programming Guide.
+Add a **4.7kΩ pull-up resistor** between VCC and DATA pin.
+
+## Supported Targets
+
+| ESP32 | ESP32-C2 | ESP32-C3 | ESP32-S2 | ESP32-S3 |
+| ----- | -------- | -------- | -------- | -------- |
+| ❌    | ❌       | ✅       | ❌       | ❌       |
+
+## Project Structure
+
+```
+dht11_reader/
+├── CMakeLists.txt          # Project configuration
+├── sdkconfig               # Build configuration
+├── main/
+│   ├── CMakeLists.txt      # Main component configuration
+│   └── main.c              # Application source code
+└── README.md               # This file
+```
+
+## Setup & Build
+
+### Prerequisites
+
+- [ESP-IDF v6.0](https://docs.espressif.com/projects/esp-idf/en/v6.0/esp32c3/get-started/index.html)
+- RISC-V toolchain (riscv32-esp-elf)
+- Python 3.13+ with virtual environment
+
+### Build Instructions
+
+```bash
+# Activate ESP-IDF environment
+source "$HOME/.espressif/tools/activate_idf_v6.0.sh"
+
+# Navigate to project
+cd temperature_measure
+
+# Build the project
+idf.py build
+
+# Flash to device (replace PORT with your serial port)
+idf.py -p /dev/ttyUSB0 flash monitor
+```
+
+## Configuration
+
+The DHT11 data pin is defined in `main/main.c`:
+```c
+#define DHT11_GPIO 0
+```
+
+To use a different GPIO, change this define and rebuild.
+
+### Reading Interval
+
+The sensor is read every 5 seconds:
+```c
+vTaskDelay(pdMS_TO_TICKS(5000));
+```
+
+Note: DHT11 requires at least 1 second between readings. Adjust as needed.
+
+## How It Works
+
+### DHT11 Communication Protocol
+
+1. **Start Signal**: MCU pulls DATA line low for 20ms, then high
+2. **Sensor Response**: DHT11 pulls line low for ~80μs, then high for ~80μs
+3. **Data Transmission**: 40 bits of data (5 bytes) in the following format:
+   - Byte 0: Humidity integer part
+   - Byte 1: Humidity decimal part
+   - Byte 2: Temperature integer part
+   - Byte 3: Temperature decimal part
+   - Byte 4: Checksum (sum of bytes 0-3)
+
+4. **Bit Encoding**: Each bit starts with a ~50μs low pulse:
+   - `0`: ~26-28μs high pulse
+   - `1`: ~70μs high pulse
+
+### Checksum Validation
+
+The checksum byte should equal the sum of the first 4 data bytes. If validation fails, the reading is retried after 1 second.
+
+## Output Example
+
+```
+Time: 2024-04-24 22:30:00
+This is esp32c3 chip with 1 CPU core(s), WiFi/BLE, silicon revision v0.4, 4MB embedded flash
+Minimum free heap size: 283488 bytes
+Humidity: 45.2%
+Temperature: 23.5°C
+Checksum valid: Yes
+```

 ## Troubleshooting

-* Program upload failure
+### Common Issues

-    * Hardware connection is not correct: run `idf.py -p PORT monitor`, and reboot your board to see if there are any output logs.
-    * The baud rate for downloading is too high: lower your baud rate in the `menuconfig` menu, and try again.
+| Issue | Solution |
+|-------|----------|
+| No sensor readings / checksum fails | Check wiring: DATA to GPIO0, pull-up resistor present |
+| Build fails with missing component | Run `idf.py fullclean` then rebuild |
+| `driver/gpio.h` not found | Ensure `esp_driver_gpio` is in PRIV_REQUIRES |
+| Linker errors with `.riscv.attributes` | Your toolchain may be too new; use ESP-IDF 6.0 compatible version |

-## Technical support and feedback
+### Debug Mode

-Please use the following feedback channels:
+To enable debug output:
+```bash
+idf.py monitor
+```

-* For technical queries, go to the [esp32.com](https://esp32.com/) forum
-* For a feature request or bug report, create a [GitHub issue](https://github.com/espressif/esp-idf/issues)
+### Hardware Connection Check

-We will get back to you as soon as possible.
+Verify your wiring with a multimeter:
+- GPIO0 should read HIGH when idle (via pull-up)
+- 3V3 is supplying power
+- GND is properly connected
+
+## Technical Details
+
+- **Sensor Range**: 0-50°C temperature, 20-90% humidity
+- **Accuracy**: ±1°C temperature, ±1% humidity
+- **Sampling Rate**: 1Hz maximum (1 reading per second)
+- **Resolution**: 1° C, 1% humidity
+
+## License
+
+This project is provided under the **CC0-1.0** license (public domain). See the SPDX identifier in the source file.
+
+## Resources
+
+- [DHT11 Datasheet](https://www.mouser.com/datasheet/2/718/DHT11-Technical-Data-Sheet-Translated-Version-1137654.pdf)
+- [ESP32-C3 Documentation](https://docs.espressif.com/projects/esp-idf/en/latest/esp32c3/)
+- [ESP-IDF Programming Guide](https://docs.espressif.com/projects/esp-idf/en/latest/esp32c3/api-guides/index.html)