FAQ

FAQ Page

1. For the memory sizes of RTEMS elements inside Chapter 8 of the processor-specific application supplement, are they in bytes or words?

They should be in bytes.

2. The Multiprocessor Communications Interface Layer describes the use of global objects as a means of communicaton, but does that mean you can use any device (serial port, CANbus, ethernet) to act as the conduit for the MPCI packets?

Yes. The only provided driver is for shared memory.

3. Can you give an example application that demonstrates the implementation of the MPCI between two nodes?

The driver portion is in c/src/lib/libbsp/shmdr. Each of the mptests is an example.

4. Has anyone implemented a JAUS message set with the RTEMS OS?

Not that I know of but I do know Robert Wade. :)

5. Does RTEMS support select() on serial ports

No. However, there is a method to register a call back on serial communications that can be used for the same effect. ioctl( fd, RTEMS_IO_RCVWAKEUP, &wakeup);

Here is a code snippet:

void receive_callback(struct termios *tty, void * arg ) {

(void) rtems_event_send( (rtems_id) arg, EVENT_RS232_RX );

}

To install the callback:

rtems_id task; struct ttywakeup wakeup;

rtems_task_ident( RTEMS_SELF, RTEMS_LOCAL, &task);

wakeup.sw_pfn = receive_callback; wakeup.sw_arg = (void *) task ;

ioctl( fd, RTEMS_IO_RCVWAKEUP, &wakeup);