Siemens S7-1200 - Page 207

Basic instructions
7.1 Bit logic operations
S7-1200 Programmable controller
System Manual, 03/2014, A5E02486680-AG
207
Set and Reset Bit Field
Table 7- 10 SET_BF and RESET_BF instructions
LAD
1
FBD
SCL
Description
Not available Set bit field:
When SET_BF is activated, a data value of 1 is assigned to "n"
bits starting at address tag OUT. When SET_BF is not
activated, OUT is not changed.
Not available Reset bit field:
RESET_BF writes a data value of 0 to "n" bits starting at
address tag OUT. When RESET_BF is not activated, OUT is
not changed.
1
For LAD and FBD: These instructions must be the right-most instruction in a branch.
2
For SCL: You must write code to replicate this function within your application.
Table 7- 11 Data types for the parameters
Parameter
Data type
Description
OUT Bool Starting element of a bit field to be set or reset (Example:
#MyArray[3])
n
Constant (UInt)
Number of bits to write
Set-dominant and Reset-dominant flip-flops
Table 7- 12 RS and SR instructions
LAD / FBD
SCL
Description
Not available Reset/set flip-flop:
RS is a set dominant latch where the set dominates. If the set (S1) and reset (R)
signals are both true, the value at address INOUT will be 1.
Not available Set/reset flip-flop:
SR is a reset dominant latch where the reset dominates. If the set (S) and reset
(R1) signals are both true, the value at address INOUT will be 0.
1
For LAD and FBD: These instructions must be the right-most instruction in a branch.
2
For SCL: You must write code to replicate this function within your application.