DIC Computer Operation. In the DIC computer
operation format, the KCMX acts as a computer to an
external peripheral device. When the computer
receives an input data request (IDR) from the device,
the KCMX will store both the request and the input data
word. Upon interrogation from the controlling
computer, the KCMX will transfer the DIC data to the
computer and send an input data acknowledge (IDA) to
the external device.
DIC Peripheral Operation. In the DIC
peripheral operation format, the KCMX acts as a
peripheral to an external computer. The KCMX
generates an ODR to the external computer. The
computer responds with data and an output data
acknowledge (ODA). The KCMX holds the data until
interrogation and transfer with the controlling
computer. The KCMX then generates another ODR to
the external computer.
DIC Interrupts. The KCMX may generate
interrupts to the controlling computer for DIC addresses
upon receipt of external function commands from the
external computer in peripheral format or external
interrupts from the external peripheral device when in
the computer format.
Sixty status signals may be received by the KCMX
(figure 13-11) via status inputs connected to KCMX
addresses 61 and 62. Each KCMX status address
provides a 30-bit status word when interrogated by the
controlling computer. The condition of each status bit
in the two status words is dependent on the condition of
its associated status relay coil. The status relays
complete the circuit between the KCMX and the
external devices generating the status signals. Supply
voltages used to generate status signals include but are
not limited to 26 vdc, 50 vdc, and 115 vac 60/400 Hz.
All 60 status lines and associated supply voltages
are connected to the KCMX via 5 status plugboards.
Each status signal relay is wired to a status signal return
line on a plugboard.
A plugboard is an electrical
connector wired with short jumper wires to provide
flexibility in the connection configuration. The
plugboards are wired when the system is installed,
depending on the system-configuration.
The control signals (figure 13-11) are generated by
the KCMX in response to control word outputs from the
controlling computer. Individual bits set in the two
control words energize relays to send control voltages
to external equipment. Once again plugboards are used
to increase system flexibility.
Ready Analog (RA) Inputs
Processing of synchro inputs (ready analog data) is
performed by the synchro multiplexer and synchro
converter logic (figure 13-1 1). The KCMX can accept
inputs from 32 three-wire synchros. Six cables are used
to connect the synchro inputs and reference voltages to
the KCMX. Five cables carry 6 synchro inputs and the
sixth carries 2 inputs and up to a maximum of 12
reference voltage inputs. The first 24 synchro channels
require 400-Hz reference voltages, while the last 8 may
use either 60-Hz or 400-Hz.
The KCMX accepts either single- or dual-speed
synchro system inputs.
The synchro multiplexer
provides the method for selecting a unique synchro
address from the 32 possible synchro inputs. The
KCMX, in response to a TDUC external function from
the controlling computer, will convert the addressed
synchro input into digital form and transmit the
digitized angle (B AM) to the controlling computer.
The digital logic in the KCMX allows a fixed time delay
for a full conversion to take place. The conversion
delay is 2 msec if a 400-Hz reference is used, or 10 msec
if a 60-Hz reference is used. A time out of the
conversion delay would cause a data word of all ONES
to be returned to the controlling computer.
A single synchro-to-digital (S/D) converter
processes the multiplexed synchro input. The S/D
converter uses the sector method to derive the precise
angle of the rotor in BAMs. The converter will perform
two separate conversions, the first for the fine speed and
the second for the coarse speed. The converter places
the combined results as a single BAM word in its output
register where the data is held until accepted by the
TDUC circuits and inputted to the controlling computer.
For single-speed synchros, both fine and coarse
conversions are performed, but the results of the fine
conversion are ignored. The bits in the BAM word that
apply to the fine conversion are left blank (ZERO).
Digital-to-Synchro (D/S) Conversion
The KCMX does not have a built in D/S conversion
capability. To provide this capability, one or more of
the DOCs must be connected to DACs.