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. Status Signals 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. Control Signals 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. 13-19