3.2.2.6 Clear interrupt
Reading from 1Ch will clear the add-on interrupt.
3.2.2.7 The analog input selection register
Address
10h
is used by the analog input channel selection
register and address
14h
is used by the analog gain control selection
register. Write 0-31 to port
10h
to select the channel number (for
differential input, write 0-15). Write 0-3 to port
14h
to select the gain
control.
Figure 3-2. Analog input control.
…
Analog inputs
…
Channel select
Analog
Mux.
Select
Gain control
ADC
AMP
Note:
1.
For single ended inputs, channels 0-31 are available. For
differential inputs, channels 0-15 are available. Input
numbers which are more than the available channel will be
discarded. Thus, for single-ended inputs, only the last 5 bits
are taken as the channel number. And for differential inputs,
only the last 4 bits are taken as the channel number.
2.
Only the last two digits are taken as the gain control code.
The gain control code and the corresponding gain is:
For PCI-1002L:
Gain code
[0 0]
[0 1]
[1 0]
[1 1]
Gain 1
2
4
8
PCI-1002 User’s Manual (Ver. 2.4, Mar./2004, PPH-015-24) ---- 30
