Siemens SIMATIC S7 - Page 108

Data Exchange with the Central Controller
4–41
IP244
C79000–B8576–C860–02
Byte 21 Main control byte 6
Value of
control bits 2
n
Logical
state
Required function
Number of standard controllers
(see below)
1
0
1
0
1
0
1
0
1
0
1
0
1
0
Free
Yes
No
Mixed operation
Recommended data format in DB: KH
Byte 21 can be transferred to the IP with the FB 162 commands "KS", "PA" or
"AE message 15".
1
0
2
0
2
1
2
2
2
3
2
4
2
5
2
6
2
7
Bit 2 1 0
Number of standard
controllers
Free
Free
Free
0 0 0 One
0 0 1 One
010 Two
0 1 1 Three
1 0 0 Four
1 0 1 Five
1 1 0 Six
1 1 1 Seven