WAGO 750-404 Manual page 38

38 • 750-404/000-003 [Frequency Counter 0.1 Hz-100 kHz]
Process Image
S0
D0
D1
D2
D3
T
VD
RANGE_SEL REQ1
RANGE_SEL REQ0
0
ST_GATE
T
VD
RANGE_SEL ACK1
RANGE_SEL ACK0
X
With the control and status byte the following tasks are possible:
Setting the Method of Measuring, Frequency Range and Representation:
The method of measuring and the representation depends on the
RANGE_SEL REQ bits in the CONTROL byte. Dependent on the adjusted
measuring method also the maximum frequency range changes.
The following table illustrates the different modes.
Input data
Status byte
Frequency value byte 0 (LSB)
Frequency value byte 1
Frequency value byte 2
Frequency value byte 3 (MSB) D3
B7 B6 B5
0 0 0
REQ Request to change the Watchdog time (T
Selection of the integration time and the representation of
measured frequency value.
Selection of the integration time and the representation of
measured frequency value.
This constant must be set to zero.
B7 B6 B5
X X ST_
GATE
Status of the GATE input (0=enabled, 1=disabled)
ACK Acknowledgement T
Acknowledgment to Range Selection, Frequency values are valid.
Acknowledgment to Range Selection, Frequency values are valid.
This value is not evaluated.
Output data
C0 Control byte
D0 Watchdog-time byte 0 (LSB)
D1 Watchdog-time byte 1 (MSB)
D2 reserved
reserved
Control byte
B4 B3
T REQ Set
VD
output
DO 2
Status byte
B4 B3
T ACK Status
VD
output
DO 2
changed.
VD
B2 B1
Set RANGE_ RANGE_
output SEL SEL
DO 1 REQ1 REQ0
) with valid data.
VD
B2 B1
Status RANGE_ RANGE_
output SEL SEL
DO 1 ACK1 ACK0
WAGO-I/O-SYSTEM 750
I/O Modules
B 0
B0