Measurement Computing USB-1602HS-2AO - Manual (Page 29)

USB-1602HS-2AO User's Guide Functional Details
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Figure 21. Typical timer/pulse generator channel
The timer outputs can be updated asynchronously at any time, however, doing so results in a pulse stream that is
not seamless.
Using detection setpoints for output control
You can configure a detection setpoint for each analog input channel. Each setpoint can update the following
channels, allowing for real-time control based on acquisition data:
 The upper 8-bits of the digital output port with a data byte and mask byte
 analog outputs (DAC 0, DAC 1)
You can configure each detection setpoint as one of the following:

Single point referenced – Above, below, or equal to the defined setpoint.

Window (dual point) referenced – Inside or outside the window.

Window (dual point) referenced, hysteresis mode – Outside the window high forces one output
(designated as Output 2); outside the window low forces another output (designated as Output 1).
Figure 22. Setpoint configuration
A digital detect signal is used to indicate when a signal condition is True or False. A signal condition is true if
the signal has met defined criteria, and false if the signal has not met defined criteria. The detect signals can be
measured as any other input channel, thus allowing real time data analysis during an acquisition.
The detection module looks at the 16-bit data being returned on a channel and generates another signal for each
channel with a setpoint applied (Detect1 for Channel 1, Detect2 for Channel 2, and so on; see Figure 23). These
signals serve as data markers for each channel's data. It does not matter whether that data is volts or counts.
A channel's detect signal shows a rising edge and is True (1) when the channel's data meets the setpoint criteria.
The detect signal shows a falling edge and is False (0) when the channel's data does not meet the setpoint
criteria. The True and False states for each setpoint criteria appear in the setpoint status register; refer to "
Using
the setpoint status register " section on page 36 for more information.
Criteria – input signal is equal to X Action - driven by condition
Compare X to: Setpoint definition Update conditions
Limit A or Limit B
 Equal to A (X = A)
 Below A (X < A)
 Above B (X > B)
(choose one)
True only:
 If True, then output value 1
 If False, then perform no action
True and False:
 If True, then output value 1
 If False, then output value 2