Chapter 3
Analog Output Timing/Control
©
National Instruments Corporation
3-39
DAQ-STC Technical Reference Manual
3.6.6.3 Board Power-up Initialization
Use this function to program software-selectable options in the secondary analog output
module of the DAQ-STC that depend on the personality of the board or device the DAQ-STC
is on. The options include polarity and pulsewidth of commonly used signals. You must
execute this function every time after you invoke the
AO2_Reset_All
function and before
you perform any analog output operation using the DAQ-STC. If you are programming a
DAQ-STC that is a part of a data acquisition system, refer to the register-level programming
manual for information about the proper selections to make in this function.
Function
AO2_Board_Personalize
{
Begin critical section;
AO_UPDATE2_Pulse_Timebase = 0 (selected by AO_UPDATE2_Pulse_Width) or
1 (selected by AO_UPDATE2_Original_Pulse);
AO_UPDATE2_Pulse_Width = 0 (3–3.5 AO_OUT_TIMEBASE periods) or
1 (1–1.5 AO_OUT_TIMEBASE periods);
AO_UPDATE2_Original_Pulse = 0 (equal to the pulsewidth of UI2_TC with a
maximum pulsewidth determined by
AO_UPDATE2_Pulse_Width) or
1 (equal to the pulsewidth of UI2_TC);
AO_UPDATE2_Output_Select = 0 (high Z) or 1 (ground) or 2 (enable, active low) or
3 (enable, active high);
End critical section;
}
3.6.6.4 Hardware Gate Programming
Use this function to enable or disable hardware and software gating. If you enable hardware
gating, you also select the signal that will control the gate, the gate polarity, and the gating
mode.
Function
AO2_Hardware_Gating
{
Begin critical section;
If (external gating is desired) then
{
AO_UI2_External_Gate_Enable = 1;
AO_UI2_External_Gate_Select = 1 through 10 (PFI<0..9>) or
11 through 17 (RTSI_TRIGGER<0..6>);
AO_UI2_External_Gate_Polarity = 0 (active high; high enables operation) or
1 (active low; low enables operation);
}
Else
AO_UI2_External_Gate_Enable = 0;
End critical section;
}
