ADLINK Technology NuDAQ ACL-8216, User Manual

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Registers Format
directly between the ACL-8216 and the PC’s memory at the fastest
possible rate, without using any CPU time. The A/D data is
automatically transferred to PC's memory after conversion
completed.
The DMA transfer mode is very complex to program. It is
recommended to use the high level program library to operate this
card. If you wish to program the software which can handle the DMA
data transfer, please refer to more information about 8237 DMA
controller.
4.2 D/A Conversion
The ACL-8216 has two unipolar analog output channels. To make
the D/A output connections from the appropriate D/A output, please
refer the following figure:
To D/A Output
D/A Converter
-
+
Ref In
-5 or -10
INT or Ext
Analog GND
Pin-30 ( AO0)
Pin-32 ( AO1)
Pin-14 ( A.GND)
The operation of D/A conversion is more simple than A/D operation.
You only need to write digital values into the D/A data registers and
the corresponding voltage will be output from the AO1 or AO2. Refer
to section 4.9 for information about the D/A data registers. The
mathematical relationship between the digital number DAn and the
output voltage is formulated as following:
Vout Vref
DAn
= − ×
4096
where the Vref is the reference voltage, the Vout is the output voltage,
and the DAn is the digital value in D/A data registers.
Before performing the D/A conversion, users should care about the