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6
1514 13 12 1110 9 87 6 5 43 2 1 0 P
CMO
1553 BUS
3.4±.5s
1.1±.2s
STATUS
10.5±.5s
NBGT
INCMD
DTREQ
DTACK
100-150ns
825-925
2.1s max
200ns min
300ns max
100-150ns
450-550ns
200-400ns
note 7
100ns max
4.8s
100ns min
50ns min
475-550ns
50ns min
225-275ns
DTGRT IS
RECOGNIZED
STATUS INPUTS
STROBED IN
250ns min Setup time
HOLD TIME 600ns min
SRQ
BUSY
SSFLAG
ADBC
RTFLAG
START OF NEW
COMMAND WORD
INITIALIZATION
A10-A0
ARE VALID
(COMMAND
WORD)
COMMAND WORD
TRANSFER TO
SUBSYSTEM
ILLCMD STROBED IN
A4-A0 0(CURRENT
WORD COUNTER)
RTU REQUESTS DATA
BUS FOR COMMAND
WORD TRANSFER
STATUS WORD
TRANSFERRED TO
ENCODER REGISTERS
NO MORE
CONTINUOUS DATA
ENCODER
STARTED UP
ENCODER REGISTERS
AVIALABLE FOR NEXT
WORD RTU
REQUESTS DATA BUS
FOR 1st DATA WORD
TRANSFER (RTFAIL
IS CLEARED IF IT
WAS SET)
825-925ns
2.2sec
note 7
100ns max
COMMAND WORD SUBADDRESS FIELD
COMMAND WORD COUNT = 00000
50ns min
DTGRT
R/W
DTSRT
A10(T/R BIT)
DAT/CMD
PREVIOUS
MESSAGE
A9-A5
PREVIOUS
SUBADDRESS
PREVIOUS
WORD COUNT
WORD
COUNT
A4-A0
D15-D0
STATEN
BITEN
HS FAIL
RT FAIL
100ns max
9.35
TRANSMIT 2 WORDS
FIGURE 3. TRANSMIT TIMING DIAGRAM