CT2553 Datasheet, PDF (12/36 Pages) Aeroflex Circuit Technology – CT2553 / 2554 / 2555 / 2556 Advanced Integrated MUX (AIM) Hybrid FOR MIL-STD-1553

TIME TAGGING (OPTIONAL)
The CT2553 will automatically access an external,
3-state device (i.e., counter) at the start and end of
each message in BC or RTU modes. The CT2553
output, TAGEN (pin 76), enables the device's output
onto the common, 16-bit data highway while
executing a memory-write cycle. The device's value
is written into the second location of the Descriptor
Stack Entry. If a counter is used its clock, enable,
and reset control lines are connected per system
requirement (See Figure 15). If no external device is
attached to the data bus, an expected value of FFFF
(H) will be written into the Time Tag location within
the Descriptor Stack.
Note that the 8-bit Time Tag value generated in the
1553 MT mode of operation is implemented using
an 8-bit counter internal to the CT2553 (See MT
operation).
CPU
DATA BUS
D15 - D00
THREE-STATE
COUNTER
OE
TAGEN
DATA
BUS
D15 - D00
OE
IOEN
CT2553
Figure 15 – BC/RT Tagging (Optional)
CONTROL
WORD
CONTROL
WORD
CONTROL
WORD
CONTROL
WORD
CONTROL
WORD
CONTROL
WORD
CONTROL
WORD
CONTROL
WORD
BROADCAST
COMMAND
(NO DATA)
RECEIVE
COMMAND
TRANSMIT
COMMAND
RECEIVE
COMMAND
MODE
COMMAND
MODE
COMMAND
MODE
COMMAND
BROADCAST
COMMAND
BROADCAST
COMMAND
LOOPED
BACK
BROADCAST
COMMAND
(NO DATA)
DATA WORD
1
DATA WORD
2
TRANSMIT
COMMAND
LOOPED
BACK
STATUS
RECEIVED
TRANSMIT
COMMAND
TRANSMIT
COMMAND
LOOPED
BACK
DATA WORD
MODE
COMMAND
LOOPED
BACK
MODE
COMMAND
LOOPED
BACK
DATA WORD
1
DATA WORD
LOOPED
BACK
STATUS
WORD
STATUS
WORD
DATA WORD
2
DATA WORD
LAST
DATA WORD
1
STATUS
WORD 1
FROM XMTR
STATUS
WORD
DATA WORD
RECEIVED
MODE CODE
WITHOUT
DATA
DATA
WORD LAST
DATA WORD
LAST
LOOPED
BACK
DATA WORD
2
DATA WORD
1 RECEIVED
MODE CODE
WITH DATA
RECEIVE
DATA BLOCK
FORMAT
MODE CODE
WITH DATA
TRANSMIT
DATA BLOCK
FORMAT
STATUS
RECEIVE
DATA WORD
LAST
DATA WORD
2 RECEIVED
DATA WORD
LOOPED
BACK
BROADCAST
COMMAND
WITH DATA
Aeroflex Circuit Technology
RECEIVE
TRANSMIT
DATA BLOCK DATA BLOCK
LAST DATA
WORD
RECEIVED
STATUS
WORD 2
FROM
RECEIVER
REMOTE
TERMINAL TO
REMOTE
TERMINAL
DATA BLOCK
Figure 16 – BC Message Formats
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SCDCT2553 REV B 8/6/99 Plainview NY [phone]