PCI-1202/1602/180x Series Card
Multi-Function Boards
User Manual/ Ver. 4.8/ Mar. 2015/ PMH-0014-48/ Page: 88
7.4
The Settling Time
If the
channel number
or
gain factor
is changed, the hardware need
extra time for signal ready
.
This is called the settling time. This limitation will apply both to the
Fixed-channel mode
and
MagicScan mode
of AD conversions. So the user must take care to avoid the settling error. In the
MagicScan mode, the MagicScan controller will control all details. The MagicScan controller will
change the channel number and gain control just after every pacer trigger signal.
Therefore the
limitation is “settling time <= pacer timer” in MagicScan mode.
7.5
When to Delay the Settling Time
In the software trigger mode, the software operation is given as follows:
1.
send software trigger pulse
2.
delay for the settling time
3.
read the A/D data
The
P180X_DelayUs(...)
is a machine independent timer function. Therefore this function is suitable
to delay the settling time. In the pacer trigger mode, the software does not have to call
P180X_DelayUs(...) The only limitation is that the pacer timer must be longer than the settling time.
Refer to
Sec. 7.1
for settling time details.
