21
2. In 2nd cycle only 4 blocks will be executed
….Block#01,02,03,05
3. In 3rd cycle only 4 blocks will be executed ….
Block#01,02,03,,05
4. In 4th cycle all blocks will be executed ….
Block#01,02,03,04,05
5. In 5 th cycle only 4 blocks will be executed
….Block#01,02,03,05
6. In 6th cycle only 4 blocks will be executed ….
Block#01,02,03,,05
7. In 7th cycle all blocks will be executed ….
Block#01,02,03,04,05
4.2 Control
Word
Another way of controlling Block execution is use of Control Word. This feature is
extremely useful for small applications where less than 17 blocks are required.
Control Word can be enable or disable while configuration of Gateway using
Configuration Software. Normally Control Word is disable. It can enable just by
clicking on check box in setup software. Control Word can be chosen from any of
the Device connected.
When Control Word is disable Block execution is totally control by Repeat
Cycle. But Repeat Cycle can only decides priority. Blocks, which are more
important for process has to be, assigned high priority and those, which are less
important for process has to be, assigned low priority.
When Control Word is enable Block execution is controlled using discrete
bits of that word,
Bit0 in control word controls execution of Block 1
Bit1 in control word controls execution of Block 2
Bit2 in control word controls execution of Block 3
Bit3 in control word controls execution of Block 4
Bit4 in control word controls execution of Block 5
.
.
.
.
Bit15 in control word controls execution of Block 16
Bit = OFF will stop execution of block
Bit = ON will enable execution of block
This feature allows user to execute block in gateway whenever required, from
outside. This avoids unnecessary execution of block and results in improvement
of speed.