I am implementing a uart communication, where i have various functions and/or tasks which may want to perform transmission using uart. Hence prior to new transmission on uart, i want to ensure that the resource (uart) is not already in use. this can be achieved by a binary semaphore whose value can be checked prior to new transmissions. But keil RTOS doesnt have sem_getvalue, in absence of which i am unable to think of any way of implementation.
one way around is to have a global flag. But currently trying to use any idea by which i can avoid using a global flag. In case of no other way, will have to use global flag.
any suggestions?
before sending a new command or the poll, in absence of reply from slave...