SemaphoreHandle_t xSemaphore = NULL; void vATask( void * pvParameters ) { // Create the semaphore to guard a shared resource. As we are using // the semaphore for mutual exclusion we create a mutex semaphore // rather than a binary semaphore. xSemaphore = xSemaphoreCreateMutex(); if( xSemaphore != NULL ) { if( xSemaphoreGive( xSemaphore ) != pdTRUE ) { // We would expect this call to fail because we cannot give // a semaphore without first "taking" it! } // Obtain the semaphore - don't block if the semaphore is not // immediately available. if( xSemaphoreTake( xSemaphore, ( TickType_t ) 0 ) ) { // We now have the semaphore and can access the shared resource. // ... // We have finished accessing the shared resource so can free the // semaphore. if( xSemaphoreGive( xSemaphore ) != pdTRUE ) { // We would not expect this call to fail because we must have // obtained the semaphore to get here. } } } }
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NXP tweet showing LPC5500 (ARMv8-M Cortex-M33) running FreeRTOS. Meet Richard Barry and learn about running FreeRTOS on RISC-V at FOSDEM 2019 Version 10.1.1 of the FreeRTOS kernel is available for immediate download. MIT licensed. View a recording of the "OTA Update Security and Reliability" webinar, presented by TI and AWS. Careers
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