Siemens SINUMERIK 840C - Manual (Page 1011)

12 Functional Descriptions 12.93
12.22.2 Functional description
Cam values
All cam values are contained in the setting data 7000 to 7007. This range is referred to as the
cam value block and includes the positions of eight cams which are divided into four cam
pairs.
Position negative cam 1
Position positive cam 1
Position negative cam 2
Position positive cam 2
Position negative cam 3
Position positive cam 3
Position negative cam 4
Position positive cam 4
SD 7000
SD 7001
SD 7002
SD 7003
SD 7004
SD 7005
SD 7006
SD 7007
Cam value
block
Pair of cams 1
Pair of cams 2
Pair of cams 3
Pair of cams 4
The cam positions must refer to the relevant machine system, in either metric system or
inches. They are input into the machine-related actual value system. No check is performed to
ensure that the cam positions do not exceed the maximum traversing range.
In axis follow-up mode, the actual positions are used as cam signals. The setpoint is used in
the case of position-controlled axes.
The cam values can be entered in the setting data display "Position measuring signals" or
written and read by means of a @-function. The cam positions can be read in the PLC
program and changed from the PLC program by means of PLC interfaces FB61 and FB62.
The user can monitor write access to the cam value block through appropriate setting of DB48
DR1, bit 5.
The changed cam positions are not activated until a 0/1 signal edge change in the TRANSFER
CAM VALUES signal (DB 48 DR0.7). As an acknowledgement of transfer, the user receives
the CAM VALUES TRANSFERRED signal (DB 48 DR1.7). He must then reset bit DB48
DR0.7.
TRANSFER CAM VALUES
DB48 DR0.7
CAM VALUES TRANSFERRED
DB48 DR1.7
A A
S S
A -> as a function of PLC program
S -> as a function of system
1
0
1
0
12–236 © Siemens AG 1992 All Rights Reserved 6FC5197- AA50
SINUMERIK 840C (IA)