Omega OMB-DAQBOARD-3000 Manuale Utente

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Detecting Input Values 
All setpoints are programmed as part of the pre-acquisition setup, similar to setting up the analog path, 
debounce mode, or counter mode setup.  Since each setpoint acts on 16-bit data, each has two 16-bit 
compare values:  Limit A (High Limit) and Limit B (Low Limit).  These limits define the setpoint 
window. 
There are several possible conditions (criteria) and effectively 3 update modes, as can be seen in the 
following configuration summary. 
 
Setpoint Configuration Summary 
◊  16-bit High Limit   
Identified as “Limit A” in software
 
◊  16-bit Low Limit   
Identified as “Limit B” in software
 
◊ Criteria:  
 
 
 
Inside window   
Signal is below Limit A and Above Limit B
 
 
 
Outside window 
Signal is above Limit A, or below Limit B
 
 
 
Greater than value 
Signal is above Limit B, Limit A is not used 
 
 
Less than value 
Signal is below Limit A, Limit B is not used
 
 
 
Equal to value 
Signal is equal to Limit A, Limit B is not used.  Note that the 
Equal to mode 
is intended for use with counter or digital input 
channels [as the source channel].  
See the TIP below.
 
 
 
Hysteresis mode 
Outside the window high forces Output 1 until an outside the 
window low 
condition exists; then Output 2 is forced.  Output 2 
continues until an outside the window high condition exists.  
The cycle repeats as long as the acquisition is running in 
Hysterisis mode. 
◊ Update Mode: 
   
Update on True Only 
   
Update on True and False 
   
None - Do not update 
◊  16-bit DAC value, P2C value, or Timer value when input meets criteria 
◊  16-bit DAC value, P2C value, or Timer value when input does not meet criteria 
◊  Type of Action: 
 
 
None 
 
 
Update P2C (see note) 
 
 
Update DACx 
 
 
Update TImerx 
 
 
By software default, P2C comes up as a digital input.   If you want the P2C signal 
to be a digital output [in some initial state before an acquisition is started] and 
P2C is to be updated by set point criterion, then you must do an asynchronous 
write to P2C before the acquisition is started.  The initial value will only be output 
if the asynchronous write to P2C has been performed. 
 
 
When using setpoints with triggers other than immediate, hardware analog, or  
TLL, the setpoint criteria evaluation will begin immediately upon arming the 
acquisition.   
 
 
TIP:  It is recommended that the “Equal to Limit A” mode only be used with 
counter or digital input channels as the channel source.  If similar functionality is 
desired for analog channels, then the “Inside Window” mode should be used. 
 
DaqBoard/3000 Series User’s Manual
 907994
 
Setpoint Configuration for Output Control      6-3