YASKAWA CPU 314ST, Manual

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Address Access Assignment
+10 Word Analog input CH3
+12 Word Analog input CH4
Used area
Ä
‘Output area’ page 96
Address Access Assignment
+4 Word Analog output CH0
+6 Word Analog output CH1
The analog values are represented in two’s complement format. Depending on the para-
metrized transformation speed the lowest value bits of the measuring value are irrelevant.
With increasing sampling rate, the resolution decreases. The following table lists the res-
olution in dependence of the sampling rate. The lowest value irrelevant bits of the output
value are marked with "X".
Resolution Analog value
High byte (byte 0) Low byte (byte 1)
Bit number 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Significance sign
2
14
2
13
2
12
2
11
2
10
2
9
2
8
2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
15bit + sign sign Relevant output value (at 3.7 ... 30Hz)
14bit + sign sign Relevant output value (at 60Hz) X
13bit + sign sign Relevant output value (at 120Hz) X X
11bit + sign sign Relevant output value (at 170Hz) X X X X
9bit + sign sign Relevant output value (at 200Hz) X X X X X X
For the sign bit is valid:
n Bit 15 = "0": à positive value
n Bit 15 = "1": à negative value
As soon as a measuring value exceeds overrange respectively unterrange, the following
value is returned:
n Measured value > overrange
–
32767 (7FFFh)
n Measured value < unterrange
–
-32768 (8000h)
At wire break, parametrization error or deactivated analog part the measuring value
32767 (7FFFh) is returned.
With this record set 9Eh you may de-activate the digital respectively analog part. Please
regard that in spite of the de-activation of the digital res. analog part, the process image
for both components remains reserved. The record set has the following structure:
Numeric notation in Sie-
mens S7 format
Algebraic sign bit (sign)
Behavior at errors
De-activate analog part
VIPA System 300S +
Deployment I/O periphery
Analog part
HB140 | CPU | 314-6CF23 | en | 19-01 98