Data Translation DT9816 Series, User Manual

Page: 60 / 108

Chapter 5
60
Specifying One or More Analog Input Channels
You can read data from one or more analog input channels using an analog input channel list
and continuous scan mode.
Using software, specify the channels you want to sample. You can enter up to six entries in the
channel list for this module. Group the channels in the list sequentially (starting either with 0
or with any other analog input channel) in ascending order. You cannot specify the same
channel more than once in the list.
Refer to page 62 for more information about continuous scan mode.
Input Ranges and Gains
DT9816 Series modules provide an input range of ±10 V. Use software to specify the range as
±10 V with a gain of 1 for an effective range of ±10 V, or specify a gain of 2 for an effective
input range of ±5 V.
Note: You must set the gain to the same value for all channels, even if you are using a subset
of the channels.
Input Sample Clock Sources
DT9816 Series modules allow you to use one of the following clock sources to pace analog
input operations in continuous mode:
• The internal A/D sample clock
• An external A/D sample clock
The following subsections describe the internal and external A/D sample clocks in more
detail.
Internal A/D Sample Clock
You can pace an analog input operation on a DT9816 Series module using an internal clock
source. Using software, specify the clock source as internal, and then specify the clock
frequency at which to pace the operation. The supported frequencies depend on the model
you selected, as shown in
Table 5 .
Table 5: Supported Clock Frequency
Model Minimum Frequency Maximum Frequency
DT9816 and DT9816-OEM 60 Hz 50 kHz
DT9816-A 60 Hz 153.846 kHz
DT9816-S and DT9816-S-WTR 183.1 Hz 750 kHz