Appendix A: Communication A.5 Communication Area Mapping
493-0736-11 (6-2) 295
The registers only hold integer values. To be able to write and read K using
communication, a simple conversion must be made:
K
COMLI
= K*100
which means that
1 ≤ K
COMLI
≤ 10000
Example
Send the value K1 = 0.87 to loop one.
Procedure:
1 Convert the value into integer format by multiplying by 100:
K1
COMLI
= K1*100 = 0.87*100 = 87
2 Send the converted value to R96.
Writing TI and TD
TI and TD are stored in two registers each. When writing either TI or TD, the
value is not stored in the controller’s PID-table until the lower part of the value is
written to the unit. This means that when writing a two-register value, the most
significant part must be written first, and the the least significant part must be
written last.
Example 1
Send the value TI1 = 125.7 seconds to loop one.
Procedure:
1. Convert the value in milliseconds into hexadecimal format:
(125 700
10
= 0001 EB04
16
)
2. Split the hexadecimal value into two 16-bit words:
(0001
16
and EB04
16
)
3. Write the MSW (most significant word) to the first register of TI1...
(Write 0001
16
, or 1
10
to R97)
4. ... and write the LSW (Least Significant Word) to the second register of TI1
(Write EB04
16
, or 60 164
10
to R98)
First write the value 100 000
10
to register R97, and then the value 25 700
10
to
register R98.
Example 2:
Send the value TD2 = 2.6 seconds to loop two.
To Next Page
Loading...
