Owner's manual

Glossary
80
proprietary programming and
networking protocols, and special-
purpose digital and analog I/O ports.
Plug and Play ISA A specification prepared by Microsoft,
Intel, and other PC-related companies
that will result in PCs with plug-in
boards that can be fully configured in
software, without jumpers or switches
on the boards.
Port A communications connection on a
computer or a remote controller.
Postriggering The technique used on a DAQ board to
acquire a programmed number of
samples after trigger conditions are
met.
Potentiometer An electrical device the resistance of
which can be manually adjusted; used
for manual adjustment of electrical
circuits and as a transducer for linear or
rotary position.
Pretriggering The technique used on a DAQ board to
keep a continuous buffer filled with
data, so that when the trigger
conditions are met, the sample includes
the data leading up to the trigger
condition.
Programmed I/O The standard method a CPU uses to
access an I/O device-- each byte of
data is read or written by the CPU.
Propagation Delay The amount of time required for a
signal to pass through a circuit.
Proportional
Control A control action with an output that is
to be proportional to the deviation of
the controlled variable from a desired
set point.
Protocol The exact sequence of bits, characters
and control codes used to transfer data
between computers and peripherals