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WHAT'S NEW
Simplifying Authenticated Cloud Connectivity for Any Device.
How Wi-Fi and Cellular connectivity modules with ExpressLink can help create secure cloud connected devices. See the blog post.
Designing an energy efficient and cloud-connected IoT solution with CoAP.
A client/server, request/response, UDP-based protocol for efficiency and cloud compatibility. See the blog post.
Introducing FreeRTOS Kernel version 11.0.0:
A Major Release with Symmetric Multiprocessing (SMP) Support. See the blog post.
FreeRTOS Roadmap and Code Contribution process.
The FreeRTOS roadmap and code contribution process are now published here and on GitHub. See the blog post.
OPC-UA over TSN with FreeRTOS.
A development project to give applications consistent access to hardware TSN capabilities. See the blog post.

FreeRTOS_open()

[FreeRTOS-Plus-IO API]

FreeRTOS_IO.h 
Peripheral_Descriptor_t FreeRTOS_open( const int8_t *pcPath, const uint32_t ulFlags );

Opens a peripheral for use with FreeRTOS-Plus-IO. The board support package defines which peripherals are available on any particular platform.

Parameters:

pcPath   The text name of the peripheral being opened, as defined by the board support package.

ulFlags   Mode flags. This parameter is not currently used. It is included for two reasons - so the FreeRTOS_open() prototype complies with the standard open() prototype, and to ensure backward compatibility after future FreeRTOS-Plus-IO developments.
Returns:

NULL if the peripheral could not be opened, otherwise a variable of type Peripheral_Descriptor_t that can be used to access the opened peripheral in future calls to FreeRTOS_read(), FreeRTOS_write() and FreeRTOS_ioctl().

Example usage: 



/* FreeRTOS-Plus-IO includes. */

#include "FreeRTOS_IO.h"



void vAFunction( void )

{

/* The Peripheral_Descriptor_t type is the FreeRTOS-Plus-IO equivalent of a descriptor. */

Peripheral_Descriptor_t xOpenedPort;



    /* Open the SPI port identified in the board support package as using the

    path string "/SPI2/".  The second parameter is not currently used and can

    be set to anything, although, for future compatibility, it is recommended 

    that it is set to NULL. */

    xOpenedPort = FreeRTOS_open( "/SPI2/", NULL );



    if( xOpenedPort != NULL )

    {

        /* xOpenedPort now contains a valid descriptor that can be used with

        other FreeRTOS-Plus-IO API functions. */

        

        . . .

    }

    else

    {

        /* The port was not opened successfully. */

    }

}




FreeRTOS_open() example
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