Siemens Simatic S5-101U Programming Instructions Manual

SIEMENS

Pr~gramma~ble Controller

Programming Instructions

Order No.: GWA 4NEB 810 2120-02 a

Fig.

1

S5-101U programmable controller

CONTENTS Page Page

THE PROGRAMMING LANGUAGE

4.2.1

STEP 5 programming language

1.1

4.2.2

Program structure

1.1

4.2.3

PRINCIPLE

OF

OPERATION 4.2.4
OF THE PC
Program processing 2.1

"RUN

and "STOP" modes 2.2 5.

Memor i es 2.2 5.1

5.1.1

NOTES

ON

PROGRAM

DEVELOPMENT 5.1.2

Power-up 3.1 5.1.3

Battery mon

i

tor i ng 3.2 5.1.4

Ren ten

tive/non-rententive 5.1.5

flags 3.2 5.1.6

Interrupt processing 3.2
Intercompatibi

l

i

ty between 5.1.7

LAD,

CSF and STL 3.4 5.1.8
Operation in the SINEC L1 3.7 5.2
local area network 5.2.1

5.2.2

PROGRAM START-UP 5.2.3
Loading and dumping a

5.2.4

program

4.1

5.2.5

Program test

4.2

6.

Search function
Signal status display
Forcing of outputs and
flags

Forcing of timers and
counters

PROGRAMMING EXAMPLES
Basic operations
Binary logic operations
Setting/resetting operations
Load and transfer operations
Timer functions
Counter functions
Comparison (relational)
operations
Arithmetic operations

Other functions
Supplementary operations
Logic operations (word mode)
Conversion functions
Shift operations
Jump operations
Cond

i

t

i

on codes

OPERATION SET

1.

The

programming language

1.1

STEP 5 programming language

The user programs are written in the
STEP 5 programning language. The

statements of this

l

anguage permit
not only the programning of simple
binary functions but also the pro­gramming of complex digital functions.
Depending on the programmer used, all
three methods of representation

statement list (STL)
1 adder d

i

agram (LAD)

control system flowchart (CSF)
are possible so that the method of
programming can be adapted to the
particular application. Only STL pro­gramming is possible with the hand­held 605U programmer. The machine

code generated by the 6701675 pro-

grammers is identical for all
three methods of representat ion

..

1.2

Program structure

The user program consists of up to

1024

statements and can be written as a pro­gram block (PB) or function block (FB).

WFy

PBl

at

FBI

can

k

exwwted

on

%c

S5+1O1U

programable

contrallsr,

Program block

A program block can be programmed and

documented in

a11 three methods of re-

presentation (STL, LAD and CSF).

A

pro­gram block can be translated from one
method of representation into the two
other methods with the 6701675 program­mers provided certain programming rules

are observed (see Section

3.4).
For users famil far with contactors and
re1 ays, the LAD method is recommended

since the ladder diagram has very close
similarities with schematic circuit

diagrams.
Program blocks are used especially

when a CRT-based

programmer is avail­able and programming or documen­tation is to be made in graphic form.

Fig.

2:

Methods of representation with
the STEP 5 programming language

to

3lN

19 239

idrcftl

Function block
Function blocks can only be written

and documented in STL form.
Jump operations make

it

possible to
enhance the structuring of the user
program and thus also its capabilities.
Short, constant response times to inter-

rupts can be implemented with load and
transfer operations in conjunction with
jump operations (see Section

3.4).

Note: Supplementary operations must

not be used in

PB1.

+o

2lh

19 239

Idrcctl

to

KC

117-15

DIN

L3

705

DIN

40

719

DIN

19

23i

,

lrrlfti

2.

Principle

of

operation

2.1

Program

processing

The control functions of the lOlU are
defined by a user program.

In order to be able to scan the user

program cyclically statement by state-

ment, the CPU

has to perform the follow-

ing functions:

1.

In the case of a cold restart (power
switch from

"Off"

to "On" or mode

selector from "Stop" to "Run"), the

process output image* is erased,

i.e.

all outputs are set to zero.

2.

The process input image* is updated,

i.e. all signal statuses of the in­puts are scanned and written into
the process input image.

The user program

(PB1 or FBI) is
scanned and processed statement by
statement. When scanning the signal

statuses of the inputs, the

CPU

ac­cesses the process input image and
not the actual inputs. When latching
and unlatching the outputs (coils),
only the process output image is
overwritten to begin with.

4. Once the user program has been pro­cessed, the process output image

is transferred to the actual out-

puts.

5.

Points 2, 3 and 4 are handled cycli­cal

ly.

Cold restart

Cr>

Erase process

output image

I

Cycle checkpoint

Read

process

input image

12nd statement

I

Last statement

H

Transfer process

I

output image to

the outputs

Fig.

3:

Principle of operation of the
S5-101U

A

scanning operation from cycle check­point to cycle checkpoint takes approx.
70 ms for 1024 statements (binary).
If

a scanning cycle is not completed

within 300 ms due to program errors

*

Process 1/0 image:

or faults, an internal monitor responds,

Internal memory area in which the

the PC enters the "Stop" status and

signal

status

("0" or "1") of the

all outputs (coils) are switched off.

inputs/outputs is stored.

The

"Run"

and "Stop" modes

"RUN" mode

p-

In the "RUN" mode, the program is scanned
cyclically from cycle checkpoint to
cycle checkpoint. The PC is brought
into the "RUN" mode by

-

switching the mode selector to

"RUN1'

-

selecting the "PC RUN1' function of
the

programner (mode selector in "RUN"

position)

-

and on recovery of the power supply

if

the mode selector is at "RUN" and

was in the "RUN" position prior to

the power failure.

Memories

The PC has an internal program memory,

the data of which can be supported for
three years by a backup battery.
There are also two different memory
submodules (see Fig. 4).

"STOP" mode

In the "STOP" mode, the program is not
scanned and the outputs (coils) are
disabled. While the PC is in the "STOP"
state, all timers and counters and the
process 1/0 image retain the values
or states they had in the last scanning
cycle prior to the PC entering the "STOP"

state.

If

the PC is switched to "RUN",

the timers and counters (0

...

7) are

reset. The non-retentive flags and the
process 1/0 image are erased.
The

PC

is brought into the "STOP" mode

by

-

switching the mode selector to "STOP"

-

selecting the "PC STOP" function on

the programmer

-

faults or errors in program scanning,
e.g. time-out or operations that can
not be interpreted by the PC.

The cause for the PC entering the 'STOP"

state can be traced with the aid of
the "DISPLAY ESTACK" function of the

programner (see Section 4.2 of Operating

Instructions).

The memory submodules are used for pro-

gram dumping or for copying the program

should only one memory submodule be

used for a number of

PCs.

On

power-up or when the PC is switched

to

"RUN",

the contents of the memory

submodule are always copied into the

internal memory and processed there.

Fig. 4: Differences between the EPROM and EEPROM submodules.

Memory submodu

l

e

Program
dump

Program

erasure

Program mod

i

-

fication via
programmer

EPROM
PG

615 (with adapter 984-2UAll)
PG 670 (with adapter 984-OUAll)
PG 675

Only with special UV lamp
(erasure time: 30 min)

On

1~

erasure of entire
program possible

EEPROM
PG 615

PG 670 (without 984

adapter)

PG 675

Direct in the PC with
the above programmers
and the PG 605U

pro-

9

r

amme

r

Programmer function:

PG PC)

possible

3.

Notes on program development

Power

up

When the power supply is switched on
or on recovery of the power supply after

a power failure,

the PC assumes the
following states without having to
take any additional measures in the
user program:

Fig.

5:

Automatic mode setting
following power-up

Prevention of automatic restart in
general

Flag* F 63.7 can be used to prevent

automatic restart on power-up.
This flag is set by the operating
system of the PC on power-up

if

the

"RUN"

mode is set

and

was set
prior to power-down. In order to
enable manual restart, flag F 63.7

is reset in the "STOP" mode.

It

can

also be reset by the user program (e.g.

in conjunction with an input signal).

Error

i

dent

i

-

f

ier* set

-

YE

S

--------t

I

NO

Operating mode
of PC prior to

power-up

STOP

RUN

POWER OFF

l

POWER ON

*

Internal re1 ay equivalent

Operating
mode

follow-

i

ng power-up

-

STOP
STOP
S

TOP

-

RUN

Current position
of mode selec­tor of the PC on
power-up

-

STOP

L

RUN

Programning example

)+

F63.7;

"1"

I

I

User-

!

I

I---

F 63

7

&

"9"

l

I

*

A

fault has occurred in program scanning
and the reason for this is stored
in the interrupt stack.

Preventinq automatic restart on battery

fail

ure

Flag F 63.6 can be used to prevent auto­matic restart on battery failure (reten­tive flags reset).
Flag F 63.6 is set by the operating

system of the PC on power-up

if

the
backup battery fails or is not connec­ted. The PC must be set to the "RUN"

mode in this case.

Flag F 63.6 is reset by the "ERASE

PROGRAM" function or by the user pro-

gram (e.g. in conjunction with an input
signal).

Programming example

3.2

Battery

monitoring

Flag F 63.6 is used for monitoring the

The PC must be in the "RUN" state.

battery.

Flag F 63.6 is reset by the "ERASE PRO-

This flag is set by the operating system

GRAM"

function of the programner or by

of the PC on power recovery and during

the user program. The user can therefore

the normal scanning cycle

if

failure determine how the PC is to react to

of the battery backup

v01 tage

is detected.

backup battery fail ure.

The

S5-101W has a total of 512 flags.

The flag area is subdivided as follows:

Retentive flags (F

0.0

...

F

31.7)

-

retain their last state prior to

-

power-down on power-up (with backup
battery only)

-

retain their last state when the

mode is changed from "STOP" to "RUN"

(with and without backup battery)

-

are reset like the non-retentive
flags on power-up (without backup

battery)

-

can also be reset by the user pro­gram

(

"

ERASE PROGRAM" function

).

By using retentive flags, the last
status of the plant or machine prior

to the PC leaving the "RUN" mode can

be stored. On restart, the plant or
machine can resume operations at the
point at which

it

was stopped.

Interrupt processing

When an interrupt signal (e.g. emer-

gency off) from the process is re-

ceived by the PC, the latter inter­rupts cyclic scanning of the user program

and inititates the processing of a

specific interrupt routine.

Interrupt processing with the

S5-101U

is defined exclusively by the user pro­gram so that each input and output can

be used for interrupt processing.

Non-retentive flags (F 32.0.. .F 63.7)

-

are reset when the PC mode changes
from "STOP" to "RUN" and on power-up.

Flags F 61.0

-

F 62.7 are reserved

as coordinating

fl

ags for operation
in the SINEC L1 local area network;
flags F 63.0

-

F 63.7 are reserved
as system flags. Since they are af­fected by the PC operating system,
they must not be used as flags in
the normal sense.

In order to achieve minimum response
times, the inputs and outputs are re­ferenced direct, i.e. outside cyclic
program scanning. The

load/transfer

operations "LPB" (inputs) and "TPB"

(outputs) are available for this pur­pose.

A

more or less constant response time

is achieved

if

the scanning of the in-

puts

programmed by the user as interrupt

inputs is uniformly distributed over
the entire user program. Fig. 6 shows

a user program with interrupt processing.

Task: When input

I

0.0

becomes

"l",

outputs

Q

@.g.

..

Q

0.7

are to assume

the state of flags F

3.a

...

F3.7. In

order to keep the response time as
short and constant as possible,

ten

interrupt scans should be written in

the user program.

User

program

STEP

5

program (STL)

Interrupt

routine

Expl

anat ions

1st interrupt scan: by loading PB

0,

I

0.0

is scanned direct, i.e. by­passing the process image, and mapped
on F

@.a.

If

F

0.0

(and consequently

I

0.0)

is

"l",

a jump is made to the

interrupt routine.

F

10.0

defines the

return address.

2nd

i

nterrupt scan

10th interrupt scan

Flag byte FB3 is transferred direct into

peripheral byte PB

0,

i.e. direct to
the outputs. The process output image
is updated.

By scanning flags

F

10.0

...

F 11.0 (only
one flag is used), the user program is
continued at the return address last
defined.

Fig.

6:

Example of a user program with interrupt scanning

3.5

Intercompatibility between LAD, CSF and STL

General

Each of the methods of representa­tion in the STEP

5

programming
languages has specific properties
and limitations.
Consequently, a program block written

in STL cannot simply be displayed as
an LAD or CSF and the graphic methods
of representation, LAD and

CSFy may

not always be fully compatible.

In other words, one form cannot al­ways be translated back into the

other form.

If

the program has been entered as

Fig.

7:

Range and limitations of the

an LAD or CSF,

it

can always be trans- methods of representation in the

lated back into STL form. STEP

5

programming language

Input Output

The aim of this section is to establish

a number of rules, which,

if

adhered to,

will

ensure complete compatibility be-

tween the three methods of representation.
These rules are classified as follows:

-

Rules for compatibility between the
graphic methods of representation
(LAD and CSF)

.

If

these rules are followed, input is
possible in one graphic form and display
in the others.

Fig.

8:

Graphic input

I

nput Output

-

Rules for compatibility between the

statement list and the graphic methods
of representat ion.

If

these rules are observed,

it

is

possible to enter a program in any

if

the three methods of representation,
graphic or not, and to have

it

dis-

played in the other two forms.

Fig.

9:

Input

in the form of

a statement list

Input as LAD and dis~lav as CSF (STL)
Rule: Do not exceed the display

boundaries for LAD.
Excessive nesting may cause the LAD
display boundary to be exceeded

(8

levels)

max

.4

Example of maximum LAD nesting for display as CSF

Input as CSF and display as LAD

(STL)

Rule

1:

Do not exceed the display
boundaries for LAD.
Too many inputs on a CSF box cause
the

l

adder diagram display boundary

to be exceeded.

CSF

Fig.

11:

Example of a maximum

AND

box in CSF form for display as an LAD

Rule 2: The output of a complex ele-

ment (memory, comparator, timer and

counter) must not be

ored.

Fig. 12: Only AND boxes are allowed in.CSFs after a complex element.

In~ut as STL and display as LAD or CSF

Rule

1:

A

complex element must not have

In addition, every unused input or

out-

a preceed i ng operation.

put must be assigned an NOP

0 operation.

Rule 2: The inputs and outputs of

com-

In the case of timers and counters, the

plex elements must be programmed in

set input and the input for loading the

the order in which they are assigned

time (TW) or count (ZW) must be

dis-

parameters on the screen in graphic

abled together.

mode.

Times and counts are exceptions since
the relevant value must first be stored

in the accumulator with a load operation.

STL

LAD

CSF

Fig. 13:

Example for assigning NOP operations to unused inputs and outputs

3.6

Operation in the SINEC

L1

local area network

The SINEC L1 local area network is used
for interconnecting

programnabl e con-

trol

l

ers of the l ow-end performance
range and operates on the Master-Slave
principle.
The CP 530

comrnun i cations processor

is always the Master, and the slaves

the

CPUs of all small PCs. Each slave

is assigned a

s1 ave number under which

it

is referenced. Data can be inter-

changed between the master and up to
30 slaves, as well as between the indi­vidual slaves. In the case of the

S5-101U,
the slave number, the coordinating flags
and the send and receive mailboxes are
defined as follows:

Slave

numk

The slave number is stored at the beginning

of the user program

(PBlIFB1) together

with an indentifier.

In addition to the actual data, control
and security information, which the
STEP 5 user program can access through
a coordinating flag word, is also trans-

mi

tted

.

The actual data are deposited in a receive
mailbox and a send mailbox which the
user can access with load and transfer
operations.

header

SF

63.0

LKF

..

Identifier

Nos.

1...30

RECEIVE coordinatinq

fl

aq b.yte (KME)

SEND coordinating

fl

aq byte (KMS)

Flag byte FB

61

is used. Flag byte FB

62

is used.

M61.7

.

.

.

M 61.0

I

I

1-r~

Receive error in last transfer

ERROR with master

SLAVE

FAIL A slave in the network has failed

BUS-RUN BUS is in RUN state

PG-BIT Programmer requests the bus access

INTERRUPT This message is accompanied by an interrupt

EMPF-ERK Operating system may accept data from the bus into

the receive

mailbox

Bit from bus master

M62.7

.

M

62.0

Send error In last transfer

Slave permits programmer access

SEND-ERK User releases send

mailbox for sending to the bus

Bit for bus master

The coordinating flags are affected by the operating system of the PC and

can therefore not be used as flags in the normal sense.

Receive mailbox
The receive mailbox is in data block

DB1 (DW 40

...

DW72) and has the following

structure

:

l) Slave No.

0

=

Master

DL 40

DL 41

DL 42

DL 71

DL 72

Send

mailbox

The send mailbox is in data block DB 1 (DW88..

.DW

112) and has the

following structure:

LENGTH of net

(0..

.64)
1st i tern of data
3rd item of data

61st item of data
63rd item of data

l) Slave No.

0

=

Master

DR 40

DR

41

DR

42

DR 71

DR

72

DL 80

DL 81
DL 82

DL

111

Nett
data

Nett
data

SOURCE-SLAVE No.

(0..

.30)
2nd item of data
4th item of data

62nd

i

tem of data

64th

itemof data

LENGTH of nett data

(0..

.64)

1st item of data

3rd item of data

61st item of data

For more detailed information on the SINEC L1 local area network, please refer to the

Instructions

(4NEB 811-0545) and Programming Instructions (4NEB 811-0546) of the SINEC L1

network

.

DW 40

DW 41

DW 42

DW 71
DW 72

DL 112 63rd item of data

DR

112

DR

80

DR

81

DR 82

DR

111

p

p-

64th item of data DW 112

DESTINATION SLAVE No.

(0..

.30)
2nd item of data
4th

i

tern of data

62nd item of data

.-

DW 80

DW 81
DW 82

DW

111

4.

Program Start

=up

The hand-held PG 605U/615 programmer

The following settings are necessary

and the CRT-based PG 670 and PG 675

on the PG 670 and PG 675 programners

programmers can be used for loading

in conjunction with the

S5-1101 U pro-

and testing programs. grammable controller:

PG 670:

S5-150

AK

S5-130

W

PG 675: S5-150

S

NO

4.1

Loading and dumping a program

Fig. 14: Schematic of a program loading operation followed by the

dumping of the program in an EEPROM submodule

4.1

Before loading the program, the "ERASE

When the program has been loaded,

it

PROGRAM"

function must be executed.

is transferred from the

programmer memory

This deletes to the internal memory of the

PC.

If

-

the internal program memory of the PC

an EEPROM submodule is plugged in, the

-

the binary process

I/O

image

program is automatically dumped.

-

all flags

Once the program has been transferred

-

error identifiers and the causes of

to the PC memory,

it

is no longer in

interrupts.

the programner memory and must be brought

back into the latter before program

corrections can be made*

(output

FBl/PBl)

.

Dumping of the program in an EPROM sub-

module is possible on the PG 615 (with

adapter), PG 670 (with 984 adapter)

and PG 675 programmers.

To dump the program

in

an EPROM sub-

module, proceed as shown in Fig. 14.

Put PC to STOP

r-------

*

I

I

Dump program

Erase program

I

t

I

\Ir

Load program

I

Put PC to STOP

into

programmer

1

i

I

$

I

Transfer pmgram

Carry out any

pro-

I

from programmer gram corrections

Transfer program'

from

PC

to pro-

*

4

I

grammer

to

PC

JI

JI

-

Transfer program'

I

Plug EEPROM

from PC to pro-

I

submodule

in

Set

PC

to RUN

grammer

L

*

JI

4

I

r

I

Tmnsfer pmg-am

I

from programmer

Test pmgram

Set

PC

to STOP

+

JI

I

to

Pc

'b

2

T

I

\

.

I

.

r

Is program execu-

I

4

I

t

ing properly?

I

J

R

Necessary only in the case
of the

605U

progmmmer End

Wait until program-

ming is completed