Miteq D-9301, Operation And Maintenance Manual, Page: 30 / 86

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3.3.2.7 RS422/485 Bus Termination (See Figure 3-2)
Jumper selectable, 120 ohm termination resistors are connected
across the DATA IN +/- and DATA OUT +/- terminals. Installing E1
places the resistor across the DATA OUT terminals and installing
E2 places the resistor across the DATA IN terminals.
3.3.2.8 Contact Closure Control
Inputs to the rear panel interface connector (J6) are
continuously scanned for momentary closures. When a closure is
detected the converter will tune to one of 16 pre-selected
frequencies stored in memory locations 01 through 16. This
operation requires the converter to be in remote operation modes.
Momentary connection of F"nn" to COM will cause the converter to
tune to the frequency stored in memory location "nn".
3.3.2.9 IEEE 488 Control
The 9300 Series Converter performs the basic Talker and Listener
functions as specified in IEEE Standard 488. It is also capable
of sending a Service Request to the IEEE 488 controller and will
respond with a status word when the Serial Poll Enable message is
received.
3.3.2.9.1 Device Address/Service Request Enable
The device address is set with the ADDRESS DIP switch on the rear
panel. S1, 2, 3, 4 and 5 select the address assignment in binary
(switch off = "1", on = "0", S1=LSB). Switch 8 enables the
Service Request feature (switch off = disabled, on = enabled).
S6, 7 are spares.
The Service Request feature is only available in converters
equipped with the Status Alarm Readout option.
3.3.2.9.2 Data Input Messages
The messages to and from the converter are ASCII character
strings terminated with CR, LF and EOI.
3.3.2.9.2.1 Frequency Set
The Frequency Set message sets the converter to the specified
frequency in kHz and also unmutes the converter.
F14000500 (8 digit)
F3700125 (7 digit)