Crown Audio PSI - Manual (Page 6)

Page 6
IQ–PSI IQ Pocket Serial Interface
Fig. 2.1 Front and Bottom Views of an IQ–PSI
2 Facilities
A. Power Switch
This two-position sliding switch turns the unit on and off.
Slide the switch toward the serial cable to turn it on. When
first turned on, the green Enable indicator (D) will glow
brightly and the yellow DSPI (C) will “wink” twice to show
that adequate voltage is available.
B. RS232 Computer Connector & Cable
A female 9-pin “D-shell” connector and 16-inch (41-cm)
cable is provided for serial connection to a host com-
puter. The RS232 communication standard is supported.
Note: A 9-pin to 25-pin adapter will be required if the
serial port of the host computer has only a 25-pin connec-
tor.
The IQ–PSI is configured so that if an active computer
is plugged into the RS232, the PSI detects that the RTS is
high and functions automatically as an interface; with no
computer detected, it functions as an
IQ component.
C. DSPI
This yellow DSPI (Data Signal Presence Indicator)
flashes when the
IQ–PSI sends or receives a valid IQ
command. It can also be forced to stay on as an aid to
rapid troubleshooting of Crown Bus wiring. In addition,
when the
IQ–PSI is switched on, the DSPI will “wink”
twice to show that adequate voltage is available. The
absence of adequate voltage could indicate a low bat-
tery, defective AC power adapter or an AC mains low-
voltage condition commonly referred to as a “brownout.”
D. Enable Indicator
This green LED lights whenever the power switch (A) of
the unit is turned on and power is available.
E. External 10 VDC Power Connector
Connect the external AC power adapter (included with
domestic units only) to this male coaxial DC power con-
nector. It requires a plug with an outside diameter (O.D.)
of 5.5 mm and inside diameter (I.D.) of 2.1 mm. The
external power adapter should provide from 8.5 to 15
VDC at 300 mA.
Note: The center conductor of the plug
should carry the positive voltage. No battery is required
when an external AC source is used. If desired, interna-
tional customers should provide their own external AC
power adapter which is appropriate for the AC input
C D E F G
A B
AUX
CROWN BUS
10 VDC IN
1718
W
. M
is
hawaka Rd
.
Elkhart, IN 465
17
U
.S
.A.
ENABLE
DSPI
RS232
POWER
POCKET SERIAL INTERFACE