Example - WAGO 750-404 Manual

40 • 750-404/000-003 [Frequency Counter 0.1 Hz-100 kHz]

Example

Attention
The range of the watchdog timer stretches from 0 to 16383ms (0x0000 to
0x3FFF) in steps of 1ms per digit. Values which raise the permitted range of
the watchdog timer are masked with 0x3FFF.
Set Outputs:
Bits 2 and 3 set the additional two outputs of the counter module.
2.1.4.8 Example
Changing the Method of Measurement, Frequency and Representation:
The frequency counter is set to a measurement range of 1 Hz ... 100 kHz with
a resolution of 1/10 Hz and 16 measurement periods.
14.Set the new measurement range with the bits 0 and 1 (RANGE_SEL REQ
Output bit
Value
15.Wait for the feedback from the counter module in the status byte, bit 0 and
Input bit
Value
16.After the expiration of the delay the current frequency value with the
Input data
Value
0 and 1) in the control byte.
B7
0
1 (RANGE_SEL ACK 1 and 0). The status byte has the following bits:
B7
X
adjusted resolution then appears in the input data with the following data
bytes D0 to D3:
Control byte
B6 B5 B4
X X X
Status byte
B6 B5 B4
X X X
Data bytes
D3 D2
0x.. 0x..
B3 B2 B1
X X 0
B3 B2 B1
X X 0
D1 D0
0x.. 0x..
WAGO-I/O-SYSTEM 750
I/O Modules
B0
1
B0
1