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page 413

Non-edge triggered

TON, TRO, TOF, ADD, MUL, etc.

24.2.1 Basic Data Handling

• Some handy functions found in PLC-5’s (similar functions are available in other PLC’s)

24.2.1.1 - Move Functions

• There are two types of move functions,

MOV(value,destination) - moves a value to a memory location MVM(value,mask,destination) - moves a value to a memory location, but with a mask to

select specific bits.

• The following function moves data values between memory locations. The following example moves a floating point number from floating point memory 7 to 23

MOV

Source F8:07

Destination F8:23

• The following example moves a floating point number from floating point memory F8:7 to integer memory N7:23

MOV

Source F8:07

Destination N7:23

• The following example puts an integer value 123 in integer memory N7:23

page 414

MOV

Source 123

Destination N7:23

• A more complex example of the move functions follows,

 

 

 

MOV

 

 

 

source 130

 

 

 

 

 

 

dest N7:0

 

 

 

 

 

 

 

 

 

 

 

MOV

 

 

 

source N7:1

 

 

 

 

 

 

dest N7:2

 

 

 

 

 

 

 

 

 

 

 

MVM

 

 

 

source N7:3

 

 

 

 

 

 

mask N7:4

 

 

 

dest N7:5

 

 

 

before (binary)

after (binary)

N7:0

0000000000000000

N7:0

0000000010000010

N7:1

1101101101010111

N7:1

1101101101010111

N7:2

0000000000000000

N7:2

1101101101010111

N7:3

1101100010111011

N7:3

1101100010111011

N7:4

1010101010101010

N7:4

1010101010101010

N7:5

0000000000000000

N7:5

1000100010101010

24.2.1.2 - Mathematical Functions

These functions use values in memory, and store the results back in memory (Note: these functions do not use variables like normal programming languages.)

Math functions are quite similar. The following example adds the integer and floating point number and puts the results in ‘F8:36’.

page 415

ADD

source A N7:04 source B F8:35 destination F8:36

Basic PLC-5 math functions include, ADD(value,value,destination) - add two values SUB(value,value,destination) - subtract MUL(value,value,destination) - multiply DIV(value,value,destination) - divide NEG(value,destination) - reverse sign from positive/negative CLR(value) - clear the memory location

Consider the example below,

page 416

ADD

source A N7:0 source B N7:1 dest. N7:2

ADD source A 1

source B N7:3 dest. N7:3

SUB

source A N7:1 source B N7:2 dest. N7:4

MULT

source A N7:0 source B N7:1 dest. N7:5

DIV

source A N7:1 source B N7:0 dest. N7:6

NEG

source A N7:4 dest. N7:7

CLR dest. N7:8

DIV

source A F8:1 source B F8:0 dest. F8:2

DIV

source A N7:1 source B N7:0 dest. F8:3

addr.

before

after

N7:0

10

10

N7:1

25

25

N7:2

0

35

N7:3

0

1

N7:4

0

-10

N7:5

0

250

N7:6

0

2

N7:7

0

10

N7:8

100

0

F8:0

10.0

10.0

F8:1

25.0

25.0

F8:2

0

2.5

F8:3

0

2.0

Note: integer values are limited to ranges between -32768 and 32767, and there are no fractions.

• As an exercise, try the calculation below with ladder logic,

page 417

N7:2 = -(5 - N7:0 / N7:1)

Some intermediate math functions include, CPT(destination,expression) - does a calculation ACS(value,destination) - inverse cosine COS(value,destination) - cosine ASN(value,destination) - inverse sine SIN(value,destination) - sine ATN(value,destination) - inverse tangent TAN(value,destination) - tangent XPY(value,value,destination) - X to the power of Y LN(value,destination) - natural log LOG(value,destination) - base 10 log SQR(value,destination) - square root

Examples of some of these functions are given below.

page 418

given A = ln B + eC acos ( D)

assign

A = F8:0

B = F8:1

C = F8:2

D = F8:3

It can also be done with a compute expression

LN

SourceA F8:1

Dest. F8:4

XPY

SourceA 2.718

SourceB F8:2

Dest F8:5

ACS

SourceA F8:3

Dest. F8:6

MUL

SourceA F8:5

SourceB F8:6

Dest F8:7

ADD

SourceA F8:4

SourceB F8:7

Dest F8:7

SQR

SourceA F8:7

Dest. F8:0

CPT

Dest. F8:0

Expression

SQR(LN(F8:1)+XPY(2.718,F8:2)*ACS(F8:3))

page 419

• For practice implement the following function,

 

 

y + log ( y)

x = atan y

------------------------

y + 1

 

• Some functions are well suited to statistics.

AVE(start value,destination,control,length) - average of values STD(start value,destination,control,length) - standard deviation of values SRT(start value,control,length) - sort a list of values

• Examples of these functions are given below.

page 420

AVE

File #F8:0

Dest F8:4 Control R6:1 length 4 position 0

STD

File #F8:0

Dest F8:5 Control R6:2 length 4 position 0

 

 

 

SRT

 

 

 

File #F8:0

 

 

 

 

 

 

Control R6:3

Addr.

before

after

length 4

position 0

 

 

 

F8:0

3

1

 

 

F8:1

1

2

 

F8:2

2

3

 

F8:3

4

4

 

F8:4

0

2.5

 

F8:5

0

1.29

 

There are also functions for basic data conversion. TOD(value,destination) - convert from BCD to binary FRD(value,destination) - convert from binary to BCD DEG(value,destination) - convert from radians to degrees RAD(value,destination) - convert from degrees to radians

Examples of these functions are given below.

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