SrFlipFlop - Function Block

The Sr Flip Flop function block prioritizes the set input if both the inputs are "true". Sr Flip Flop is a one-bit functional block

Sr Flip Flop function block has two inputs:

The RS stands for Set or Reset. With the help of the Reset input, the flip-flop is reset to its original state, and the output is either logic level "1"or logic level "0". It is determined by the flip-Set flop's or Reset state. It can be "FLIPPED" into one logic state or "FLOPPED" back into another.

The basic NAND gate SR Flip Flop circuit is used to store the data and thus provides feedback from both of its outputs back to its inputs. The Sr Flip Flop has three inputs that relate to its current state: Set, Reset, and Out (current output

Figure 1: SrFlipFlop - Function Block

Figure 2: SrFlipFlop - Property Sheet

Inputs with value "true" or "null" are not evaluated. The output keeps on last value.

Figure 3:SrFlipFlop - Logic Diagram

Truth table

Set

Reset

Output

false

false

No change or remains in previous state.

false

true

false

true

false

true

true

true

true

Table 1:Truth table of RsFlipFlop Function

Input

Input Name

Description

Set

This is a Boolean point input slot. It has a priority, if both inputs are "true".

Reset

This is a Boolean point input slot.

Table 2:Inputs of SrFlipFlop Function

Output

Output Name

Description

Out

Output = "true" or "false" depending on the input and reset value.

Table 3:Output of SrFlipFlop Function

Parameter

Parameter Name

Description

Out Save

Master Sync Enabled : If you set it to "true" the last output will be set as output for one cycle after the controller restarts. The application can use it to return to the same state before the controller restart.

Out: To enable or disable the Out feature.

Table 4:Parameter of SrFlipFlop Function

Examples

1.       Set and Reset are set to "true", Out is set to "true".

Figure 4: Set and Reset "true",Out "false".

2.       Set and Reset are set to "false", Out will be retained the last state.

Figure 5: Set and Reset "false", Out last state.

3.       If Set = "true" and Reset = "false", Out = "true".

Figure 6: Set "true"and Reset "false", Out "true".

4.       If Set = "false" and Reset = "true", Out = "false".

Figure 7: Set "false"and Reset "true", Out "false".

Refer to General Description for general information about IRMN4 Function Blocks.