Siemens CPU 948, Programming Manual

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Timer value With the operation L KT, you can load a timer value directly into
ACCU 1 or indirectly from a flag or data word. The value must have
the following structure (with L KT, you specify the time base after the
period in the operand as shown below):
Example
Note
The start of each timer is liable to an inaccuracy of 1 time base!
When using timers, you should therefore select the smallest
possible time base (time base < timer value):
Example:
time value 4s not:
1 s x 4 inaccuracy: 1 s
but: 0.01 s x 400 inaccuracy: 0.01 s
You want to set a time of 127 sec.:
Bit assignment:
Timer value 127
0 1 1 1
0 0
0
0 0
0 0 x x
1
1 1
1
7 2 2
Irrelevant
Time base 1 sec
Bit no.
Timer value 0 ... 999 in BCD
0 1 2 3 4 5 6 7 8
9
10 11 12 15 14 13
2
10 10
0
10
1
These bits are irrelevant
(i.e. they are ignored when
the timer is started)
Time base specified in BCD: 0: 0.01 sec
1: 0.1 sec
2: 1 sec
3: 10 sec
Basic Operations
CPU 948 Programming Guide
C79000-G8576-C848-04
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