Process data area

 Auswahl Hilfen previous top next english version

Easy Profibus ► EPB Functional Description ► Process data area

 

Peripheral addressing

 

The structure of the peripheral areas for the EasyProfibus is as follows:

 

3 permanently allocated words

+ fault message area

+ variable area

 

Structure in detail:

 

Word

ProfibusDP Input (SPS PA)

Info

ProfibusDP Output (SPS PE)

Info

1

LEDs F1-F16

LEDs can only be switched on or off; blinking is not possible

F-keys F1-F16

image of keyboard +1

2

control word "static"

image of  control word "static"

Enter / ESC /

Cursorkeys  & Passbit

image of keyboard +0

3

Text number SET

Page call via PLC

Text number ACTUAL

Output current page number

IN/OUTPUT area  (max 64 Bytes = 32 Words) = 512 fault messages

4

Error 1..16

fault message area

Receipt 1..16

Receipt area

5 to xx

Error 17 to 512

fault message area

Receipt 17 to 512

Receipt area

IN/OUTPUT area  (min 2 Bytes max. 110 Byte) = 55 word variables



ACTUAL VALUE

SET VALUE

4

VAR I1

Variable with  address 1

VAR O1

Variable with  address 1

5

VAR I2

Variable with  address 2

VAR O2

Variable with  address  2

6 to  max.

etc.

etc.

 

 

The full length and thus the number of possible fault messages and variables of the existing peripheral area depends on the number (length) of words defined in the DP slave.

The more words have been defined, the more fault messages and / or variables (up to the maximum limit) can be used. Please note, however, that the more words have been defined / are being used, the longer the refresh of pages and the updating of variables will take.

The same applies to the number of dynamic objects on a page: the more there are, the slower the page refresh and the variable update.

 

Since the variable area is located after the fault message area, the maximum possible number of variables (as well as the defined word length of the DP slave participant) is defined by the fault message area.

The more fault messages have been defined, the fewer variables can be used.

The maximum number of variables is 55 words, provided no fault messages are being used.

 

 

<< return