Rsf_ - Rs Flip-Flop; Rtg_ - Rising Edge Trigger - Siemens 353 User Manual

UM353-1B

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).
RS FLIP-FLOP TRUTH TABLE
R S
R
1 X
Reset
.
S 0 1
Set
0 0
0 0
R - RESET Input
S - SET Input
X (don't care)
BLOCK DIAGRAM

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).
P
.
April 2012
LO O1
X 0
O1
Output 1
X
1
1 1
0 0
LO - Last Output
O1 - Output
Output 1
Pulse Input
BLOCK DIAGRAM
RS FLIP-FLOP
R
Reset
S
Set
P U L A S
I P U
N T
I N P U T
E S N
.
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.
RISING EDGE TRIGGER
Pulse Input P
O1
.
I N P U T
E S N
Function Blocks
RSF_ ESN = 000
O1
RS FLIP-FLOP Output 1
T
Power Up LAST ................... NO/YES (YES)
(S)
R
INPUT R ...........
(H) loop tag.block tag.output
S
INPUT S ...........
(H) loop tag.block tag.output
Exec. Seq. No. .................. 001 to 250
(H)
RTG_ ESN = 000
RISING EDGE
O1
Output 1
TRIGGER
P
INPUT P ........
loop tag.block tag.output
(H)
Exec. Seq. No. .............. 001 to 250
(H)
(null)
(null)
(null)
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