TM 11-5820-333-30
2-12. LOCAL CONTROL OPERATION. Continued
Local fill is initiated by the operator. The ECCM module puts a 6.75 V negative pulse on the FILL REQ line. The
FILL INFO is input from the fill device. It is a serial data stream that contains the variables to be stored in the ECCM
module. The FILL VA is a clock signal from the fill device. The interface module buffers the signals. FILL VA is
processed into FILL CLK and FILL DETECT. FILL CLK follows FILL I/A. When the fill device is attached, FILL l/A is
detected, and FILL DETECT drops to logic 0.
2-13, DEDICATED REMOTE CONTROL OPERATION
The dedicated remote control panel interfaces between the C-11466 or C-11466A control unit and the rt. It has a
serial data interface with the rt control module and a serial data interface with the remote control unit. It receives
control and data words from the control unit, decodes them, and directs the appropriate outputs to the rt control
module. In the reverse direction, it receives display information from the rt, stores it, signals the control unit, and
transfers the information on command of the control unit,
The data control (See Figure FO-6) monitors data sent by the control unit and extracts synchronization from it.
The status register stores IFM PWR A and IFM PWR B signals for use by the optional IFM power amplifier and
STBY, STBY RESET-N, HB ON, and HB OFF signals for use by the rt power supply (para 2-5).
The data gating directs other control information to the rt control module, This information includes FUNCTION
switch position, MODE switch position, PRESET switch position, and keyboard data. Switch data is sent on the
REM DATA line accompanied by sixteen clock pulses on the REM 24 CLOCK line and one pulse on the REM 24
STROBE line. Keyboard data is sent on the REM DATA line accompanied by eight clock pulses on the REM 8
CLOCK line and one pulse on the REM 8 STROBE line.
The data buffer receives display data on the SERIAL DATA line and a 320-kHz clock on the DISP CLOCK line,
stores the data, and signals the remote control unit through the remote control interface. The remote control unit
generates a 640-Hz clock and takes the data from the data buffer through the remote control interface.
The remote control interface handles 8-bit serial data words in either direction. Data words are sent on the DATA
(+) and DATA (-) lines accompanied by a 640-Hz clock on the CLOCK (+) and CLOCK (-) lines. The DATA
DIRECTION signal from the control unit determines whether the data is an input or output.
The fill circuit is identical to that described for local control operation (para 2-12).
2-14. MIL-STD-1553B CONTROL OPERATION
The MlL-STD-1553B control panel allows control and status readout by a MlL-STD-1553B bus controller. A
microprocessor follows instructions stored in ROM to translate messages from the MlL-STD-1553B bus format to
the rt control format and vice versa. A RAM is used to store messages during message transfer. The control
panel recognizes its address on the MlL-STD-1553 bus, receives command messages, and sends status mes-
sages on command of bus controller. There are two redundant, 2-wire MlL-STD-1553B data buses. Only one bus
is active at a time.
The BUS A and BUS B connectors (See Figure FO-7) receive command words, send status words, and send or
receive data words. All words begin with three sync bits. The command word includes address bits, one bit which
determines whet her the message is transmit or receive, subaddress bits, message word count bits, and a parity
bit. Status words are transmitted only in response to command words and include address bits, status bits, and a
parity bit. Data words may be sent by bus controller or control panel. Except for the usual sync bits and parity bit,
all data word bits are used for data.
The transceivers receive and transmit phase-modulated bipolar, 1-MHz Manchester coded data through bus
coupling transformers. In receive mode, the decoder converts Manchester coded serial data to 16-bit parallel
data. Each received word is checked for valid sync field, proper Manchester coding, correct parity, and correct
address. A valid word pulse is generated if all checks are passed. In transmit mode, the encoder converts 16-bit
parallel data to serial format, adds a sync field and parity bit, and encodes the serial data in Manchester code.
Data received from the MlL-STD-1553B bus is temporarily stored in first-in-first-out (FIFO) memory. The proto-
col control circuit interfaces with the microprocessor and provides control functions for the encoder/decoder
and FIFO circuits.
2-12
