Справочник Пользователя для Mitsubishi Electronics FX5
174
19 BUILT-IN I/O FUNCTION
19.3 Pulse Width Measurement Function
19.3 Pulse Width Measurement Function
19.3
Pulse Width Measurement Function
This section describes the pulse width measurement function.
Pulse width measurement function overview
The CPU module has a built-in pulse width measurement function and it is capable of measuring the pulse width/period of a
maximum of 4 channels. The pulse width/period measurement function stores the values of 0.5
maximum of 4 channels. The pulse width/period measurement function stores the values of 0.5
s ring counters at the input
signal rising edge and falling edge to special data registers. This function also stores the difference in the counter values
(pulse width) between the rising edge and the falling edge or stores the difference in the counter values (cycle) between the
previous rising edge and the current rising edge to special data registers in units of 0.5
(pulse width) between the rising edge and the falling edge or stores the difference in the counter values (cycle) between the
previous rising edge and the current rising edge to special data registers in units of 0.5
s.
For the pulse width measurement function, input channel assignments, logical switch, and measurement mode settings are
configured with parameters, and measurements are started/stopped using the HIOEN instruction.
configured with parameters, and measurements are started/stopped using the HIOEN instruction.
To use the pulse width measurement function, parameter settings and the HIOEN instruction are always
required.
required.
Pulse width measurement specifications
This section describes the pulse width measurement function specifications.
Pulse input signals
Pulse width measurements can be used for a maximum of 4 channels.
Select from X0 to X7 for each channel, with parameter settings.
Select from X0 to X7 for each channel, with parameter settings.
■Measurement frequencies
The table below shows the measurement frequencies.
■Measurement precision
The table below shows the measurement precision.
Pulse measurements
The pulse width and period are stored in special devices by the END instruction. (Page 177 List of special relays/special
registers)
registers)
Pulse width maximum value and minimum value
The maximum value and minimum value of the pulse width from the start of measurements are stored in special devices.
(Page 177 List of special relays/special registers)
(Page 177 List of special relays/special registers)
Period maximum value and minimum value
The maximum value and minimum value of the period from the start of measurements are stored in special devices.
(Page 177 List of special relays/special registers)
(Page 177 List of special relays/special registers)
FX5U-32M, FX5UC-32M
FX5U-64M, FX5U-80M
Measurement frequencies
X0 to X5
X0 to X7
200 KHz
X6 to X17
X10 to X17
10 KHz
Item
Description
Possible measurement range
Cycle
5
s
Pulse width
5
s
Maximum measurable signal width
1073s741ms823
s
Resolution
0.5
s