Siemens CPU 948 - Page 482

Application example continued:
Implementation
1. Loading blocks
The following blocks must be loaded in the indivitual CPUs:
Function CPU 1 CPU 2 CPU 3
Restart OB
User program
FB: SEND-DAT
FB: RECV-DAT
Link list
Input DB
Output DB
OB 20
FB 1
FB 100
FB 101
DB 100
DB 5
DB 3; DX 4
—
FB 1
FB 100
FB 101
DB 100
DB 3
DB 5
—
FB 1
FB 100
FB 101
DB 100
DB 5; DX 4
—
2. Creating the link list
The link list is created and entered in data block DB 100:
DB100 LEN=37
PAGE 1
– – Sub-list 1 – –
0: KS = ’S1’; Send from CPU 1 to ..
1: KY = 001,003; .. CPU 2 (DB 3)
2: KY = 002,004; .. CPU 3 (DX 4)
3: KY = 000,000;
4: KS = S2 ; Send from CPU 2 to ..
5: KY = 001,005; .. CPU 1 (DB 5)
6: KY = 001,005; .. CPU 3 (DB 5)
7: KY = 000,000;
8: KS = ’S3’;
9: KY = 000,000;
10: KY = 000,000;
11: KY = 000,000;
12: KS = ’S4’;
13: KY = 000,000;
14: KY = 000,000;
15: KY = 000,000;
Continued on the next page
Applications
CPU 948 Programming Guide
10 - 78 C79000-G8576-C848-04