Computer Drive Installation Instructions

09.95 8 PLC Machine Data (PLC MD)

8.7 PLC MD bits for the user (user bits)

8000 to

8049

DW 0 -

DW 24

PLC MD

DB65

DW No.

Bit No.

7 6 5 4 3 2 1 0

Default value: 0

In addition to PLC MD words, PLC MD bits are also available to the user to do with as he sees

fit. The available bit area comprises 25 words (400 bits).

The PLC machine data enables the machine manufacturer to process program blocks, function

blocks or sections of a program conditionally on the basis of the bits set, and to allocate

machine-specific option bits. The user can then specify additional machine-specific values.

Sample application:

A user builds machines with different turrets, but wants to be able to provide a single program

for all machines. The turrets differ in the number of tool locations, e.g. turret 1 has 6, turret 2

has 8 locations.

The program for each type of turret (in this case a program block) is invoked via a

corresponding PLC machine data bit. In the program, the number of tool locations is specified

in PLC MD words.

OB 1

U MD1

JC PB

U MD2

JC PB

PB turret 1

PB turret 2

FB turret s

END OF SECTION

SINUMERIK 840C (IA)