| When you call TagWrite, the tag name is
checked to make sure it exists. If the tag does not exist then an
error is returned. If the tag exists then the write request is
passed to the I/O Server and the TagWrite function will return. The
actual write request will complete async to the execution of your
cicode. Because of this you cannot tell if the write has completed
by checking the return value from TagWrite. If the write fails a
hardware error will be generated so you will be notified as to the
failure of the write. The TagWrite does not return an error if the
unit is offline as the unit may come online soon and the write may
be able to be completed. The main reason for this is so that the
TagWrite can execute async writes, this greatly increases the
performance of this function. |
