# Vishay VEML6040 Sensor
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[](https://platformio.org/)
[](https://registry.platformio.org/libraries/k0i05/esp_veml6040)
[](https://components.espressif.com/components/k0i05/esp_veml6040)
This ESP32 espressif IoT development framework (esp-idf) i2c peripheral driver was developed for the Vishay VEML6040 4-channel colour I2C sensor. Information on features and functionality are documented and can be found in the `veml6040.h` header file and in the `documentation` folder.
## Repository
The component is hosted on github and is located here: <https://github.com/K0I05/ESP32-S3_ESP-IDF_COMPONENTS/tree/main/components/peripherals/i2c/esp_veml6040>
## General Usage
To get started, simply copy the component to your project's `components` folder and reference the `veml6040.h` header file as an include. The component includes documentation for the peripheral such as the datasheet, application notes, and/or user manual where applicable.
The auto-calibrate algorithms aren't consistent and are still being worked on.
```text
components
└── esp_veml6040
├── CMakeLists.txt
├── README.md
├── LICENSE
├── idf_component.yml
├── library.json
├── documentation
│ └── datasheets, etc.
├── include
│ └── veml6040_version.h
│ └── veml6040.h
└── veml6040.c
```
## Basic Example
Once a driver instance is instantiated the sensor is ready for usage as shown in the below example. This basic implementation of the driver utilizes default configuration settings and makes a measurement request from the sensor at user defined interval and prints the results.
```c
#include <veml6040.h>
void i2c0_veml6040_task( void *pvParameters ) {
// initialize the xLastWakeTime variable with the current time.
TickType_t last_wake_time = xTaskGetTickCount ();
//
// initialize i2c device configuration
veml6040_config_t dev_cfg = I2C_VEML6040_CONFIG_DEFAULT;
veml6040_handle_t dev_hdl;
//
// init device
veml6040_init(i2c0_bus_hdl, &dev_cfg, &dev_hdl);
if (dev_hdl == NULL) {
ESP_LOGE(APP_TAG, "veml6040 handle init failed");
assert(dev_hdl);
}
//
veml6040_config_register_t cfg_reg;
//
veml6040_get_configuration_register(dev_hdl, &cfg_reg);
//
ESP_LOGI(APP_TAG, "Configuration Register: 0x%02x (%s)", cfg_reg.reg, uint16_to_binary(cfg_reg.reg));
//
// task loop entry point
for ( ;; ) {
ESP_LOGI(APP_TAG, "######################## VEML6040 - START #########################");
//
// handle sensor
float red_als, green_als, blue_als, white_als;
esp_err_t result = veml6040_get_als(dev_hdl, &red_als, &green_als, &blue_als, &white_als);
if(result != ESP_OK) {
ESP_LOGE(APP_TAG, "veml6040 device read failed (%s)", esp_err_to_name(result));
} else {
ESP_LOGI(APP_TAG, "Red ALS: %.2f Lux | Green ALS: %.2f Lux | Blue ALS: %.2f Lux | White ALS: %.2f Lux", red_als, green_als, blue_als, white_als);
}
//
ESP_LOGI(APP_TAG, "######################## VEML6040 - END ###########################");
//
//
// pause the task per defined wait period
vTaskDelaySecUntil( &last_wake_time, I2C0_TASK_SAMPLING_RATE );
}
//
// free resources
veml6040_delete( dev_hdl );
vTaskDelete( NULL );
}
```
Copyright (c) 2024 Eric Gionet (<gionet.c.eric@gmail.com>)
idf.py add-dependency "k0i05/esp_veml6040^1.2.5"