DAQ-STC: Generating a Pulse Train on the FREQ_OUT Pin
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This VI generates a 50 % duty cycle TTL pulse train on the FREQ_OUT pin. This VI works with devices that have a DAQ-STC counter timer chip. Examples of these devices are the PXI-6070, PCI-MIO-16E-1, and AT-MIO-16E-2.
INSTRUCTIONS:
1. Enter the device number of your board.
2. Leave the values of FOUT port and FOUT timebase source at their defaults.
3. Change the values of FOUT timebase signal and FOUT divisor if you wish to change the frequency of the generated pulse train. The valid values for FOUT timebase signal are 10000000 and 100000. Valid values for FOUT divisor are 1-16. The frequency of the pulse train will be the FOUT timebase signal divided by the FOUT divisor. For example the default values of 100000 and 2 will generate a 50000 Hz (50 % duty cycle) pulse train. Notice that since a signal is being divided down to obtain this pulse train, dividing down by an odd number will not produce a perfect 50 % duty cycle.
4. Run the VI. With the VI running, switching the pulse train switch to on will start the pulse train and switching the pulse train switch to off will stop it. If you change any of the "input data for fout" parameters, you must switch the pulse train off and back on before the new parameters will be used.
KEY PARAMETERS:
This VI shows how to use the CTR Control.vi to generate a pulse train.
I/O CONNECTIONS:
To read the pulse train, connect to the FREQ_OUT and DGND pins.
To find the actual pin numbers, refer to the hardware user manual.
DAQ VIs USED:
CTR Control.vi
Filename: 2173.zip
Application Software: LabVIEW Full Development System 5.0.1
Language(s): LabVIEW
Hardware Group: Multifunction DAQ (MIO)
Driver: Traditional NI-DAQ (Legacy)
INSTRUCTIONS:
1. Enter the device number of your board.
2. Leave the values of FOUT port and FOUT timebase source at their defaults.
3. Change the values of FOUT timebase signal and FOUT divisor if you wish to change the frequency of the generated pulse train. The valid values for FOUT timebase signal are 10000000 and 100000. Valid values for FOUT divisor are 1-16. The frequency of the pulse train will be the FOUT timebase signal divided by the FOUT divisor. For example the default values of 100000 and 2 will generate a 50000 Hz (50 % duty cycle) pulse train. Notice that since a signal is being divided down to obtain this pulse train, dividing down by an odd number will not produce a perfect 50 % duty cycle.
4. Run the VI. With the VI running, switching the pulse train switch to on will start the pulse train and switching the pulse train switch to off will stop it. If you change any of the "input data for fout" parameters, you must switch the pulse train off and back on before the new parameters will be used.
KEY PARAMETERS:
This VI shows how to use the CTR Control.vi to generate a pulse train.
I/O CONNECTIONS:
To read the pulse train, connect to the FREQ_OUT and DGND pins.
To find the actual pin numbers, refer to the hardware user manual.
DAQ VIs USED:
CTR Control.vi
Requirements
Filename: 2173.zip
Software Requirements
Application Software: LabVIEW Full Development System 5.0.1
Language(s): LabVIEW
Hardware Requirements
Hardware Group: Multifunction DAQ (MIO)
Driver: Traditional NI-DAQ (Legacy)
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