User manual

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7.3.1
PicoLog 1000 Series Digital Outputs control
Location:
click the Digital Outputs button on the Channels toolbar
Purpose:
controls the data logger 's built-in signal generator
Digital Outputs dialog for the
PicoLog 1216
The range of controls available depends on which model of data logger you have.
Basic controls
PWM. Some digital outputs on some devices can be set to
generate a pulse-width modulated waveform. This is a logic
signal that is toggled with a specified period and duty cycle. The
average value of the signal is proportional to its duty cycle, so it
can be processed by an external low-pass filter to produce a
signal that is proportional to the duty cycle.
Off: Set the digital output manually using the Digital
Outputs slider (see below).
PWM: Use the digital output as a PWM output with
controllable Period and Duty Cycle (see below).
Period. Select the duration of one cycle of the PWM output.
Duty Cycle. The percentage of the PWM signal period that the
signal spends at the logic high level. For example, if the period
is 1 ms and the duty cycle 25%, then the signal will spend 25%
of 1 ms = 250 s of each cycle at the logic high level, and the
remaining 750 s at the logic low level. The voltages of the logic
high and low levels are specified in the User's Guide for the data
logger, but are typically 0 volts (low) and 3.3 volts (high). Using
our example figures, the average value of the PWM output will
be 25% x 3.3 volts = 0.825 volts.
Digital Outputs
PicoLog PC Data Loggers have one or more digital outputs
capable of driving low-current loads.
Each output (unless set to PWM mode: see above) can be set to
a high or low logic level by moving the slider.
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