n
Basic parameters
Here the interrupts, the counter component should trigger, may be selected. You have
the following options:
–
None: There is no interrupt triggered.
–
Process: The counter component triggers a hardware interrupt.
–
Diagnostics and Process: With the CPU the diagnostic interrupt of the digital in-/
output periphery is only supported in connection with "hardware interrupt lost".
n
Frequency measurement
The following parameters are relevant for frequency measurement. Parameters,
which are not listed here, are ignored by the CPU.
–
Integration time:
Integration time for frequency measurement
Range of values: 10 ... 10000ms
–
Hardware interrupt:
End of measurement (End of integration time)
When activated, with each end of the integration time, a hardware interrupt is trig-
gered.
6.7.4 SFB 48 - FREQUENC - Frequency measurement
The SFB 48 is a specially developed block for compact CPUs for frequence measure-
ment.
n
The SFB FREQUENC should cyclically be called (e.g. OB 1) for controlling the fre-
quency measurement.
n
The SFB is to be called with the corresponding instance DB. Here the parameters of
the SFB are stored.
n
Among others the SFB 48 contains a request interface. Hereby you get read and
write access to the registers of the frequency meter.
n
So that a new job may be executed, the previous job must have be finished with
JOB_DONE
= TRUE.
n
Per channel you may call the SFB in each case with the same instance DB, since the
data necessary for the internal operational are stored here. Writing accesses to out-
puts of the instance DB is not permissible.
n
With the SFB FREQUENC (SFB 48) you have following functional options:
–
Start/Stop the frequency meter via software gate SW_GATE
–
Read the status bit
–
Read the evaluated frequency
–
Request to read/write internal registers of the frequency meter.
Name
Declaration
Data type
Address
(Inst.-DB)
Default value
Comment
LADDR
INPUT
WORD
0.0
300h
This parameter is not evaluated.
Always the internal I/O periphery
is addressed.
CHANNEL
INPUT
INT
2.0
0
Channel number
SW_GATE
INPUT
BOOL
4.0
FALSE
Enables the Software gate
JOB_REQ
INPUT
BOOL
4.3
FALSE
Initiates the job (edge 0-1)
JOB_ID
INPUT
WORD
6.0
0
Job ID
JOB_VAL
INPUT
DINT
8.0
0
Value for write jobs
Description
Parameters
VIPA System 300S
+
Deployment I/O periphery
Frequency measurement > SFB 48 - FREQUENC - Frequency measurement
HB140 | CPU-SC | 313-5BF23 | en | 19-01
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