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3 typical block connections for expression block, Logic functions - book 2 expression block 8-14 – Micromod MOD: 1800P - MOD 30ML Identity Module (Version 2) Algorithms, Tables and Sequential Logic Functions User Manual

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Logic Functions - Book 2

EXPRESSION BLOCK

8-14

8.2.3

Typical Block Connections for Expression Block

Typical softwiring block structures used on softwiring diagrams are shown in Figure 8-6.

R

Selected Signal

R

Input_2

Input_3

VCI3

Result

R

VCI1

Result

Input_1

EX1

Input Selector Example

R

VCI2

Result

SELECT (Input_5)

Input_1

EX1 (BADINP=NO)

Counter Example

R

DI1

Result

R

Result

DI2

EX2 (BADINP=YES)

Count

R

RESET (Input_2)

Input_4

Logic to select value
(other expression block)

!RESET * (COUNT +
MOM(Input_1))

COUNT (Input_3)

Selector Example Notes
This example selects
between three inputs by
using another expression
block that produces a
select value. If none of the
three are selected, then
the previous input (input
4) is selected.

Counter Example Notes
This example counts a
digital input with reset
provided by another digital
input. The second
expression block is set up
to keep the first
expression from latching
quality BAD.

(SELECT==1)*Input_1+
(SELECT==2)*Input_2+
(SELECT==3)*Input_3+
(SELECT>1



SELECT>3) *

Input_4

R

COUNT

COUNT (Input_1)

TIME

GPM (Input 1)

EX1 (BADINP=NO)

Totalizer Example

R

VCI1

Result

R

Result

DI2

TIME (Input 3)

HILIM (Input 2)

EX2 (BADINP=YES)

Totalized Value

R

RESET (Input 2)

!RESET * (TOTAL + GPM * MIN)

MIN (Input 3)

Totalizer Example Notes
This example totalizes an
input (i.e. gpm) with reset
provided by a digital input.
The second expression
block is set up to keep the
first expression from
latching quality BAD.

TOTAL (Input 4)

HLSTAT (Input 1)

LAST (Input 4)

HILIM

High Limit

HLSTAT

High Limit Status

EX3

TIME (Input 1)

TIME

R

(HLSTAT * (HILIM - LAST +
TIME) + !HLSTAT * (TIME -
LAST)) / 60000.0

TM1*

Time

Figure 8-6. Typical Block Connections for Expression Block