Digi AccelePort asynchronous products provide high data throughput while keeping host CPU utilization low. One of the ways it does this is by buffering data in the adapter itself, and then processing the data in the host in large bursts, rather than as single characters.
For many applications, this method works quite well.
In some cases, however, it is important that the latency (the period of time that data spends in the adapter buffers) of character transmission and reception needs to be as small as possible. A common example of this might be in a control application where a particular event causes the transmission of a character which must be recognized immediately so that appropriate action can be taken.
If you have concerns about latency, it is possible to tune the driver to minimize latency. Care should be taken in using this option, since it may be possible to tune the driver in such a way as to reduce the overall performance of your system (for example, by flooding your host CPU with individual character processing requests).
Choose your
operating system from the table below for information on how to tune the
device driver for optimum latency.
AIX
Linux
SCO OpenServer
SCO UnixWare
Solaris
NetWare
HP-UX