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* Add vitepress tree * Update existing workflows so they dont trigger on changes in the docs path * Add nojekyll, package.json, LICENCE etc * Add crowdin docs upload/download scripts * Add docs flaw checker workflows * Used docs prefix for docs workflows * Crowdin obvious fixes * ci: docs move to self hosted runner runs on a beefy server for faster builds Signed-off-by: Ramon Roche <mrpollo@gmail.com> * ci: don't run build action for docs or ci changes Signed-off-by: Ramon Roche <mrpollo@gmail.com> * ci: update runners Signed-off-by: Ramon Roche <mrpollo@gmail.com> * Add docs/en * Add docs assets and scripts * Fix up editlinks to point to PX4 sources * Download just the translations that are supported * Add translation sources for zh, uk, ko * Update latest tranlsation and uorb graphs * update vitepress to latest --------- Signed-off-by: Ramon Roche <mrpollo@gmail.com> Co-authored-by: Ramon Roche <mrpollo@gmail.com>
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I2C Bus (Development Overview)
I2C 是一种分组交换串行通信协议，允许多个主设备连接到多个从属设备，每个连接只需使用2根电线。 它用于在短距离、板内通信中将低速外设 IC 连接到处理器和微控制器。
Pixhawk/PX4 支持：
- Connecting off board components that require higher data rates than provided by a strict serial UART, such as rangefinders.
- 与仅支持 I2C 的外围设备兼容。
- 允许多个设备连接到单个总线（有效保护端口）。 例如，LED、指南针、测距仪等。
:::info The page Hardware > I2C Peripherals contains information about how to use (rather than integrate) I2C peripherals and solve common setup problems. :::
:::tip IMUs (accelerometers/gyroscopes) should not be attached via I2C (typically the SPI bus is used). The bus is not fast enough even with a single device attached to allow vibration filtering (for instance), and the performance degrades further with every additional device on the bus. :::
集成 I2C 设备
Drivers should #include <drivers/device/i2c.h> and then provide an implementation of the abstract base class I2C defined in I2C.hpp for the target hardware (i.e. for NuttX here).
A small number of drivers will also need to include headers for their type of device (drv_*.h) in /src/drivers/ - e.g. drv_led.h.
To include a driver in firmware you must add the driver to the board-specific cmake file that corresponds to the target you want to build for. You can do this for a single driver:
drivers/sf1xx
You can also include all drivers of a particular type.
CONFIG_COMMON_DISTANCE_SENSOR=y
:::tip
For example, you can see/search for CONFIG_DRIVERS_DISTANCE_SENSOR_LIGHTWARE_LASER_I2C in the px4_fmu-v4_default configuration.
:::
I2C 驱动程序示例
To find I2C driver examples, search for i2c.h in /src/drivers/.
Just a few examples are:
- drivers/distance_sensor/lightware_laser_i2c - I2C driver for Lightware SF1XX LIDAR.
- drivers/distance_sensor/lightware_laser_serial - Serial driver for Lightware SF1XX LIDAR.
- drivers/ms5611 - I2C Driver for the MS5611 and MS6507 barometric pressure sensor connected via I2C (or SPI).
更多信息
- I2C (Wikipedia)
- I2C Comparative Overview (learn.sparkfun.com)
- Driver Framework