Advantech PCI-1710 - Manual (Page 42)

38 PCI-1710/1710HG User's Manual
the stop channel and then repeat. The following examples show the
scan sequences of the MUXs (all channels are set as single-ended).
Example 1 If the start scan input channel is AI3 and the stop
scan input channel is AI7, then the scan sequence is AI3, AI4, AI5,
AI6, AI7, AI3, AI4, AI5, AI6, AI7, AI3, AI4…
Example 2 If the start scan channel is AI13 and the stop
scan channel is AI2, then the scan sequence is AI13, AI14, AI15, AI0,
AI1, AI2, AI13, AI14, AI15, AI0, AI1, AI2, AI13, AI14…
The scan logic of the PCI-1710/1710HG card is powerful and easily
understood. You can set the gain code, B/U and S/D, for each channel.
The scan logic will be a little complex if you set the analog input
channels in differential mode, however. In differential mode, signals
are transmitted by a pair of channels, AI<i, i+1> ( i = 0, 2, 4…
14) . In each pair of differential channels, the even channel is the
positive end and the odd one is the negative end.
For example, if channel 0 is set as differential, then channel 0 and
channel 1 are combined into one channel and refer to the gain code
and B/U of channel 0 (the channel 1 values are unavailable). By the
same rule, if channel 2 is set as differential, then channel 2 and channel
3 are combined into one channel, and refer to the gain code and B/U of
channel 2 (the channel 3 values are unavailable). The following
examples show the scan sequences in differential mode.
Example 3 Suppose that the start scan input channel is AI14
and the stop scan input channel is AI3. If AI14 is differential, AI0 and
AI1 are single-ended, and AI2 is differential, then the scan sequence is
AI14, AI0, AI1, AI2, AI14, AI0, AI1, AI2, AI14…..
Example 4 Suppose that the start scan channel is AI11 and
the stop scan channel is AI15. If AI11 is single-ended, AI12 is