CCS/TMS320F28379D: Function timeout

Hello,

Thanks for your question! To answer, if your application requires polling, you could make your own "new" version of SCI_readCharArray, which adds another check to the while loop in the function. In particular, you would need to modify this while loop here:

//
// Wait until a character is available in the receive FIFO.
//
while(SCI_getRxFIFOStatus(base) == SCI_FIFO_RX0) // <- add another check here (&&) to check for a timer reaching a certain value (that you choose)
{
}

You will have to make your own timer function for this. See C2000Ware example "timer_ex1_cputimers.c" in C2000Ware_version#\driverlib\f2837xd\examples\cpu1\timer\ and chapter 3.8 of the Technical Reference Manual for details on how to make a timer.

If you are able to use interrupts instead of polling, I would recommend to instead use interrupts (see the example "sci_ex2_loopback_interrupts.c" in C2000Ware for implementing interrupts). This would avoid the need for a timeout on the communications (preventing the blocking call), and a timeout can still be implemented if needed with a timer.

Let me know if that answers your question!

Regards,

Vince

Hello,

Awesome, thanks for the follow up. That makes sense for the reasoning behind it then! In this case, then using interrupt or polling will be equivalent, as you are wanting to handle potential malfunctions in the code.

In summary, you will need a timeout, and to do so, you will have to change the circled while statement as I mentioned in the first post (clarified below for more detail):

// you will have to implement a start timeout function using
// the timer example in C2000Ware. 
start_timeout_function(...)
{
    // FILL THIS OUT TO START THE TIMER AND RESET EVERYTHING
    // SEE C2000Ware example for how to do this
}
// Then in the interrupt for the timer, you  will change a global variable 
// (called timeout_variable) to be nonzero.
// For example:
__interrupt void
cpuTimer0ISR(void)
{
    //...
    // SET UP THE REST OF THE ISR BEFORE THIS
    
    timeout_variable = 1; //or whatever error code you would like to throw
    
    // SET UP THE REST OF THE ISR AFTER THIS
    //...
}

// start the timer before the wait statement
start_timeout_function()
//
// As soon as there is data -OR- the timeout limit was passed, then exit the
// loop
//
while(SCI_getRxFIFOStatus(base) == SCI_FIFO_RX0 && timeout_variable == 0)
{
}

By doing the above, you will be able to implement a timeout to the interrupt in case of a malfunction!

Let me know if you have any follow up questions!

Regards,

Vince