beautypg.com

6 conventions used for input/output identifiers, Conventions used for input/output identifiers, 2introduction – Lenze E94A User Manual

Page 27

background image

Lenze · 9400 function library · Reference manual · DMS 6.7 EN · 08/2014 · TD05

27

2

Introduction

2.6

Conventions used for input/output identifiers

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

2.6

Conventions used for input/output identifiers

This chapter describes the conventions used for the identifiers of the inputs/outputs of the function

blocks. The conventions ensure a uniform and consistent terminology and make reading and com-

prehending the interconnection and application easier.

Tip!
The conventions used by Lenze are based on the "Hungarian Notation". This ensures that

the most significant characteristics of the corresponding input/output (e.g. the data type)

can be instantly recognised from its identifier.

An identifier consists of

• a data type entry
• an identifier (the "proper" name of the input/output)
• an (optional) signal type specification

Data type entry
The data type entry provides information about the data type of the corresponding input/output:

Identifier
The identifier is the proper name of the input/output and should indicate the application or func-

tion.

• Identifiers always start with a capital letter.
• If an identifier consists of several "words", then each "word" must start with a capital letter.
• All other letters are written in lower case.

Data type entry

Meaning

Resolution

Value range

B

BOOL

1 bit

0 ≡ FALSE / 1 ≡ TRUE

by

BYTE

8 bits1

0 ... 255

dn

DINT

32 bits

-2147483647 ... 2147483647

dw

DWORD

32 bits

0 ... 4294967295

n

INT

16 bits

-32767 ... 32767

s

STRING

-

-

t

TIME

32 bits

-

W

WORD

16 bits

0 ... 65535