NAME

       threads - creates hard realtime HAL threads

SYNOPSIS

       loadrt threads name1=name period1=period [fp1=<0|1>] [<thread-2-info>] [<thread-3-info>]

DESCRIPTION

       threads  is  used  to create hard realtime threads which can execute HAL functions at specific intervals.
       It is not a true HAL component, in that it does not export any functions, pins, or parameters of its own.
       Once it has created one or more threads, the threads stand  alone,  and  the  threads  component  can  be
       unloaded  without  affecting  them.   In  fact, it can be unloaded and then reloaded to create additional
       threads, as many times as needed.

       threads can create up to three realtime threads.  Threads must be  created  in  order,  from  fastest  to
       slowest.   Each  thread  is specified by three arguments.  name1 is used to specify the name of the first
       thread (thread 1).  period1 is used to specify the period of thread 1  in  nanoseconds.   Both  name  and
       period  are  required.   The  third argument, fp1 is optional, and is used to specify if thread 1 will be
       used to execute floating  point code.  If not specified, it defaults to 1, which means  that  the  thread
       will  support floating point.  Specify 0 to disable floating point support, which saves a small amount of
       execution time by not saving the FPU context.   For  additional  threads,  name2,  period2,  fp2,  name3,
       period3,  and  fp3  work  exactly  the same.  If more than three threads are needed, unload threads, then
       reload it to create more threads.

FUNCTIONS

       None

PINS

       None

PARAMETERS

       None

BUGS

       The existence of threads might be considered a bug.  Ideally, creation and deletion of threads  would  be
       done  directly  with  halcmd  commands,  such  as  "newthread name period", "delthread name", or similar.
       However, limitations in the current HAL implementation require thread creation to take  place  in  kernel
       space, and loading a component is the most straightforward way to do that.

LinuxCNC Documentation                             2007-01-16                                         THREADS(9)