F178_HighSpeedCounter_Measure

Input pulse measurement

This instruction measures the number of input pulses in a specified counting period and the pulse period.

Parameters

Input

s1_iHscChannel (INT)

High-speed counter channel: 0–5

s2_NumberOfPulses_iPeriodTime_ms (INT)

Counting period [ms]:

1–5000 (1ms–5s).

s1_NumberOfPulses_iNumberOfPeriods (INT)

Number of counting periods: 1–5

s1_PulsePeriod_iMeasurementMethod (INT)

Unit of pulse period measurement

0: Pulse period is not measured

1: Pulse period is measured in ms

2: Pulse period is measured in ms

3: Pulse period is measured in ms and ms

s1_PulsePeriod_iTimeoutValueOf1msUnitOutput (INT)

Time-out value of pulse period measurement [ms]:

0: no time-out

1: 100ms

2: 200ms

3: 300ms

4: 500ms

Output

d_NumberOfPulses_diAverage (DINT): Average number of pulses per counting period (no. of pulses in counting period/number of counting periods)
d_PulsePeriod_diTime_ms (DINT): Pulse periodm
d_PulsePeriod_diTime_ms (DINT): Pulse period [ms]

Characteristics of input pulse measurement

For input pulse measurement, the channel number, the counting period (1ms–5s) and the number of counting periods (1–5) must be specified. These parameters are used to calculate the average number of input pulses per counting period.
The unit of pulse period measurement ([ms], [ms] or both) can be specified.
If the measurement is in ms, the pulse period is measured and output immediately upon execution of this instruction. A maximum of approx. 174.4ms can be measured.
If the measurement is in ms, the value of the pulse period is updated after every measurement. A maximum of approx. 49.7 days can be measured. A time-out value can be specified after which the measured pulse period is set to -1 if measurement has not been completed.
During the first counting periods after starting the instruction, the measured pulse period is set to -1 until the specified number of counting periods has been reached.
If the pulse period is longer than the measurable range or if measurement has not been completed, the measured pulse period is set to -1.

General programming information

Select the high-speed counter input for the desired channel in the system registers.
Keep the execution condition TRUE for pulse measurement using this instruction.
To stop the measurement, turn the execution condition to FALSE.
When a high-speed counter instruction is executed, the high-speed counter control flag (e.g. sys_bIsHscChannel0ControlActive) for the channel used turns to TRUE. No other high-speed counter instruction using the same channel can be executed as long as the control flag is TRUE.
The instruction can be executed simultaneously on a maximum of two channels.
If both the main program and the interrupt program contain code for the same channel, make sure both are not executed simultaneously.
The status of the high-speed counter control flag or pulse output control flag may change while a scan is being carried out. For example, if the number of received bytes is read more than once different statuses may exist within one scan.

Error flags

sys_bIsOperationErrorHold (turns to TRUE and remains TRUE)

if channel number or values of the data table are outside the permissible range
if high-speed counter has not been set in the system registers
if the high-speed counter channel is already used by another high-speed counter or pulse output instruction
if the number of channels used is 3 or more

sys_bIsOperationErrorNonHold (turns to TRUE for one scan)

if channel number or values of the data table are outside the permissible range
if high-speed counter has not been set in the system registers
if the high-speed counter channel is already used by another high-speed counter or pulse output instruction
if the number of channels used is 3 or more

Example

POU header

All input and output variables used for programming this function have been declared in the POU header. The same POU header is used for all programming languages.

	VAR
		bStartMeasurement: BOOL:=FALSE;
		diNumberOfPulses: DINT:=0;
		diPulsePeriodTime_μs: DINT:=0;
		diPulsePeriodTime_ms: DINT:=0;
	END_VAR

LD body

BODY
    WORKSPACE
        NETWORK_LIST_TYPE := NWTYPELD ;
        ACTIVE_NETWORK := 0 ;
    END_WORKSPACE
    NET_WORK
        NETWORK_TYPE := NWTYPELD ;
        NETWORK_LABEL :=  ;
        NETWORK_TITLE :=  ;
        NETWORK_HEIGHT := 9 ;
        NETWORK_BODY
B(B_F,F178_HighSpeedCounter_Measure!,Instance,25,1,53,9,,?DEN?Ds1_iHscChannel?Ds2_NumberOfPulses_iPeriodTime_ms?Ds1_NumberOfPulses_iNumberOfPeriods?Ds1_PulsePeriod_iMeasurementMethod?Ds1_PulsePeriod_iTimeoutValueOf1msUnitOutput?AENO?Ad_NumberOfPulses_diAverage?Ad_PulsePeriod_diTime_μs?Ad_PulsePeriod_diTime_ms);
B(B_VARIN,,0,23,3,25,5,);
B(B_VARIN,,10,23,4,25,6,);
B(B_VARIN,,5,23,5,25,7,);
B(B_VARIN,,SYS_F178_HSC_MEASUREMENT_μs_ms,23,6,25,8,);
B(B_VARIN,,0,23,7,25,9,);
B(B_VAROUT,,diNumberOfPulses,53,3,55,5,);
B(B_VAROUT,,diPulsePeriodTime_μs,53,4,55,6,);
B(B_VAROUT,,diPulsePeriodTime_ms,53,5,55,7,);
B(B_CONTACT,,bStartMeasurement,9,2,11,4,);
L(1,3,9,3);
L(11,3,25,3);
L(1,0,1,9);
        END_NETWORK_BODY
    END_NET_WORK
END_BODY

ST body

IF (bStartMeasurement) then
  F178_HighSpeedCounter_Measure(s1_iHscChannel := 0, 
            s2_NumberOfPulses_iPeriodTime_ms := 10, 
            s1_NumberOfPulses_iNumberOfPeriods := 5, 
            s1_PulsePeriod_iMeasurementMethod := SYS_F178_HSC_MEASUREMENT_μs_ms, 
            s1_PulsePeriod_iTimeoutValueOf1msUnitOutput := 0, 
            d_NumberOfPulses_diAverage => diNumberOfPulses, 
            d_PulsePeriod_diTime_μs => diPulsePeriodTime_μs, 
            d_PulsePeriod_diTime_ms => diPulsePeriodTime_ms);
END_IF;