Siemens 353 - RSF - RS Flip-Flop; RTG - Rising Edge Trigger

UM353-1B Function Blocks
April 2012
3-83
3.2.77 RSF_ - RS Flip-Flop
RSF_ function blocks perform a reset dominant flip-flop
function as detailed in the truth table. An unused S input
will be set high (1) and an unused R input will be set low
(0).
POWER UP - During a warm start, when PU LAST is set to
YES, the block will initialize at the input/output states at the
instant power down occurred. A cold start will initialize the
input/output states to 0.
3.2.78 RTG_ - Rising Edge Trigger
RTG_ function blocks provide a high (1) output for one scan
cycle each time input P transitions from a low (0) to a high
(1).
BLOCK DIAGRAM
R
O1
S
RS FLIP-FLOP TRUTH TABLE
SR
LO O1
1
0
0
0
XX
X
1
0
10
000
1
1
S - SET
Input
R - RESET
Input
O1 - O
utput
LO -
Last
O
utput
O
utput
1
R
eset
S
et
X (don't care)
.
.
BLOCK DIAGRAM
O
utput
1
P
O1
P
ulse Input
.
.
R
eset
RS FLIP-FLOP
O1
O
utput
1
RS FLIP-FLOP
RSF_
ESN =
000
R
S
et
S
E
E
xec.
S
eq.
N
o.
(H)
.................. 001 to 250
S
T
U
P
N
I
INPUT S
(H)
...........
loop tag.block tag.output (null)
R
T
U
P
N
I
SN
INPUT R
(H)
...........
loop tag.block tag.output (null)
LPU TSA
P
ower
U
p
LAST
(S)
................... NO/YES (YES)
P
ulse Input
RISING EDGE TRIGGER
O1
O
utput
1
RISING EDGE
RTG_
ESN =
000
P
ESN
E
xec.
S
eq.
N
o.
(H)
.............. 001 to 250
P
T
U
P
N
I
INPUT P
(H)
........
loop tag.block tag.output (null)
TRIGGER