Orban OPTIMOD-AM 9300, Operating Manual

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TECHNICAL DATA ORBAN MODEL 9300
Remote Interface and RS-232 Interfaces
Located on control board
A remote interface connector and circuitry implements remote control of certain
operating modes; Optimod 9300 has eight remote contact closure inputs.
A valid remote signal is a momentary pulse of current flowing through remote
signal pins. Current must flow consistently for 50msec for the signal to be inter-
preted as valid. Generally, the 9300 will respond to the most recent control op-
eration, regardless of whether it came from the front panel, remote interface, or
RS-232.
Component-Level Description:
After being current limited by resistors, the GPI control signals are applied to
two quad optoisolators, U17, 19, and then to the control circuitry.
U12 is the RS323 port interface chip. It is socketed for easy field replacement in
the event of overload, lightning damage, etc. All other circuitry is surface-
mount and is not field-repairable.
Switch Matrix and LED Indicators
Located on display board
Eleven front panel pushbutton switches are arranged in a matrix, configured as
three columns and four rows. These switches are the primary element of the
physical user interface to the 9300 control software. The host microprocessor
controls the system setup and function of the DSP according to the switch / ro-
tary encoder entered commands, the AES status bits from the digital input signal,
the RS-232, and the remote control interface status. The microprocessor updates
the LED control status indicators accordingly.
Component-Level Description:
S1-S11 are the front panel pushbutton switches. CR11-CR15 are the front panel
LED control status indicators. The control microprocessor communicates with
these components through the General Purpose bus, which is buffered via IC3.
LED Meter Circuits
Located on display board
The meter LEDs are arranged in an 8x16 matrix, in rows and columns.
Each row of LEDs in the matrix has a 1/8 duty cycle ON time. The rows are multi-
plexed at a fast rate so that the meters appear continuously illuminated. Via the
General Purpose bus, the DSP sends meter data values to the control microproc-
essor, which sends the appropriate LED control words (eight bits at a time) to the
data latches that drive the LEDs directly.