Jonathan Cameron | 49b2fd6 | 2017-01-01 12:32:45 +0000 | [diff] [blame] | 1 | .. include:: <isonum.txt> |
| 2 | |
| 3 | ============ |
| 4 | Introduction |
| 5 | ============ |
| 6 | |
| 7 | The main purpose of the Industrial I/O subsystem (IIO) is to provide support |
| 8 | for devices that in some sense perform either |
| 9 | analog-to-digital conversion (ADC) or digital-to-analog conversion (DAC) |
| 10 | or both. The aim is to fill the gap between the somewhat similar hwmon and |
| 11 | :doc:`input <../input>` subsystems. Hwmon is directed at low sample rate |
| 12 | sensors used to monitor and control the system itself, like fan speed control |
| 13 | or temperature measurement. :doc:`Input <../input>` is, as its name suggests, |
| 14 | focused on human interaction input devices (keyboard, mouse, touchscreen). |
| 15 | In some cases there is considerable overlap between these and IIO. |
| 16 | |
| 17 | Devices that fall into this category include: |
| 18 | |
| 19 | * analog to digital converters (ADCs) |
| 20 | * accelerometers |
| 21 | * capacitance to digital converters (CDCs) |
| 22 | * digital to analog converters (DACs) |
| 23 | * gyroscopes |
| 24 | * inertial measurement units (IMUs) |
| 25 | * color and light sensors |
| 26 | * magnetometers |
| 27 | * pressure sensors |
| 28 | * proximity sensors |
| 29 | * temperature sensors |
| 30 | |
| 31 | Usually these sensors are connected via :doc:`SPI <../spi>` or |
| 32 | :doc:`I2C <../i2c>`. A common use case of the sensors devices is to have |
| 33 | combined functionality (e.g. light plus proximity sensor). |