I/O Stream#

I/O Stream can be used to read/write different formats of data to various streams.

The source files for I/O Stream platform software module are present under platform/services/iostream.

Overview#

I/O Stream is a platform module software that provides Input/Output functionalities by creating streams. Streams are abstractions allowing a uniform way to read/write data regardless of the physical communication interface.

I/O Stream offers many interfaces, see submodules for a list of all types available and their specificities.You can load multiple streams in the project and you can select the interface that must be used at runtime.Some interface type can also be instantiated, meaning that you can have multiple instances of an interface type which will be normally bound to a hardware peripheral.

Initialization#

The I/O Stream core doesn't require any initialization. Instead each stream type has their own initialization and their own configuration. See I/O Stream specific type to know more about how to initialize a stream.

Note that most stream will set itself as the default stream during their initialization. Thus the initial default stream will be the last stream initialized.

Default system-wide stream#

Multiple streams can be initialized in your application and you can configure a default stream that must be used when no stream is specified. Also note that the default stream will be used when calling printf and you can change the default stream at runtime. The following defines should be used for the default stream:

SL_IOSTREAM_STDIN SL_IOSTREAM_STDOUT SL_IOSTREAM_STDERR

RTOS - Task's default stream#

In the case of an RTOS environment, each task can set its own stream. By default, the task stream will be set to the system_wide default stream. From your task, you can change the default stream assigned to your task without affecting the other tasks' stream.

Printf#

I/O Stream provides third-party printf integrations. It can work with toolchain implementation or with the tiny printf implementation for embedded system. The printf API doesn't have an argument for specifying the stream to be used, so I/O Stream provides a printf API that takes a stream as an argument and calls the configured third-party implementation of printf.

Modules#

sl_iostream_t

sl_iostream_instance_info_t

I/O Stream CPC

I/O Stream EUSART

I/O Stream RTT

I/O Stream STDLIB Configuration

I/O Stream SWO

I/O Stream UART

I/O Stream USART

I/O Stream VUART