CT1995 Datasheet, PDF (9/25 Pages) Aeroflex Circuit Technology – MIL-STD-1553B Remote Terminal, Bus Controller, or Passive Monitor Hybrid with Status Word Control

Signal
DWSYNC
CMSYNC
NDRQ
PASMON
BCOPSTB
BCOPA
BCOPB
REQBUS A
REQBUS B
RT/BC
DBCACC
LTFAIL
ERROR
RTO
TXTO
PARER
MANER
Pin Description (Cont.)
Hybrid
Sink or Source
Signal Description
SOURCE
SOURCE
SOURCE
SINK
SINK
SINK
SINK
SINK/SOURCE
SINK/SOURCE
SINK
SINK
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
Data Word Sync - This line goes low if a data word sync and two Manchester
biphase bits are valid.
Command Word Sync - This line goes low if a command word sync and two
Manchester biphase bits are valid.
No Data Required - This line goes low if the encoder transmit buffer is full i.e.
another word is going to be transmitted. This signal is for information only and
must not be used to enable data from the subsystem.
Passive Monitor - When functioning as a Bus Controller this line acts as a
passive monitor select. The active going edge of this line will cause the
REQBUS lines to be latched and that bus, now selected will be monitored so
long as PASMON remains low. All traffic on the bus will be handed, after
validation, to the subsystem via STATSTB for status and commands words,
and RMDSTB for data words.
Bus Controller Operation Strobe - When functioning as a Bus Controller a
low going pulse on this line will initiate the selected bus controller operation on
the requested bus, using BCOPA&B and REQBUSA&B.
Bus Control Operation A - Least significant bit of the bus controller operation
select lines.
Bus Control Operation B - Most significant bit of the bus controller operation
select lines.
Request Bus A - This line,wwhen in RT mode, is the least significant bit of the
bus request lines which specify the origin of the command, ie. they are
sources. When in BC mode these lines are sinks and specify which bus is to be
used for the next command.
Request Bus B - Most significant bit of the bus request lines. (See above for
description.)
Remote Terminal/Bus Control - This line when high causes the ASIC to
function as a remote terminal. When low the ASIC functions as a bus controller
or passive monitor.
Dynamic Bus Control Accept - This line should be permanently tied low if a
subsystem is able to accept control of the bus if offered.
Loop Test Fail - This line goes low if any error in the transmitted waveform is
detected or if any parity error in the hardwired RT address is detected.
Error - This line latches low if a Manchester or parity error is detected. It is
reset by the next CMSYNC (RT mode) and also by RTO in the BC mode.
Reply Time Out - This signal will pulse low whenever the reply time for a
transmitting terminal has been exceeded. This line is intended for the bus
controller use.
Transmitter Time Out - This line goes true if the transmitter time out limits are
exceeded.
Parity Error - This line will pulse low if a parity error is detected by the
decoder.
Manchester Error - This line will pulse low if a Manchester error is detected by
the decoder.
Aeroflex Circuit Technology
9
SCDCT1995 REV A 11/21/01 Plainview NY [phone]