Crown Audio IQ-P.I.P.-SMT - Manual (Page 30)

Page 30
IQ P.I.P.–SMT
5.4 IQ System Communica-
tions
The IQ–P.I.P.–SMT communi-
cates with the host computer via
the Crown Bus. Connections to
the Crown Bus are made via the
4 and 5-pin locking DIN connec-
tors on the rear panel. IQ com-
mands entering the
P.I.P. are fed
into an input receiver circuit that
converts the 20 mA current loop
signal into a standard logic sig-
nal that the microprocessor can
understand. This signal is also
passed directly to the Crown Bus
for output where it is passed on
to the remainder of the loop. Data
sent in response to IQ com-
mands is also sent through the
Crown Bus output where it
passes through the remainder of
the loop and back to the host
computer. A “drop out” relay is
also present which makes a
physical contact between the
Crown Bus input and output con-
nectors in the event of a power
failure. This means that as long
as the Crown Bus cables are
connected to the
P.I.P. , the
Crown Bus will remain unbro-
ken—even if power to the
P.I.P.
is lost.
5.5 Microprocessor and
Reset Switch
The “brains” of the IQ–P.I.P.–SMT
are contained in the micropro-
cessor. It interprets commands
received from the Crown Bus and
responds accordingly. The
IQ–
P.I.P.–SMT is designed to provide
an “automatic reset” in the event
of a power failure, but the rear re-
set switch has also been added.
Pressing this switch restores all
P.I.P. settings to the “user de-
faults” if it is pressed for less than
2 seconds or to the factory de-
faults if it is pressed for more than
2 seconds. The only exception is
the initialization data which can
only be changed with
IQ System
software on the host computer.