Measurement Computing Personal Daq/3000 Series - Manual (Page 55)

Setpoint Configuration for Output Control 6
Overview …… 6-1
Detecting Input Values …… 6-3
Controlling Analog, Digital, and Timer Outputs …… 6-4
P2C, DAC, or Timer Update Latency …… 6-6
More Examples of Control Outputs …… 6-7
Detection on an Analog Input, DAC and P2C Updates …… 6-7
Detection on an Analog Input, Timer Output Updates …… 6-8
Using the Hysteresis Function …… 6-8
Using Multiple Inputs to Control One DAC Output
…… 6-10
The Setpoint Status Register …… 6- 11
Overview
Personal Daq/3000 Series modules include a setpoint configuration feature which allows the user to
individually configure up to 16 detection setpoints associated with channels within a scan group. Each
detection setpoint can be programmed in the following ways:
o
Single Point referenced – above, below, or equal to the defined setpoint
o
Window (dual point) referenced – inside, or outside the window
o
Window (dual point) referenced, Hysterisis Mode – outside the window high forces one
output (designated “Output 2”; outside the window low forces another output, designated as
“Output 1.”
A digital detect signal is used to indicate when a signal condition is True or False, i.e., whether or not the
signal has met the defined criteria. The detect signals themselves can be part of the scan group and can be
measured as any other input channel; thus allowing real time data analysis during an acquisition.
Each setpoint can update the following, allowing for real time control based on acquisition data:
o
P2C digital output port with a data byte and mask byte
o
analog outputs (DACs)
o
timers
The detection module looks at the 16-bit data being returned on a given channel and generates another
signal for each channel with a setpoint applied: Detect1 for Channel 1, Detect2 for Channel 2, etc. These
signals serve as data markers for each channel’s data. It doesn’t matter whether that data is volts, counts,
period, pulsewidth, timing, or encoder position.
A channel’s detect signal will show a rising edge and will be True (1) when the channel’s data meets the
setpoint criteria. The detect signal will show a falling edge and will be 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 (see page 6-11).
Personal Daq/3000 Series User’s Manual 887894 Setpoint Configuration for Output Control 6-1