National Instruments NI 9144, User Manual

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NI 9144 User Guide and Specifications
NI 9237
The vendor configuration extensions for the NI 9237 are listed in Table 85.
As a DSA module, the NI 9237 does not synchronize to other modules and free-runs at its own
fixed rate.
NI 9237 Configure Module
This module is set to maximum speed and configured for Full-Bridge mode for all channels by
default.
Table 85.
NI 9237 Vendor Configuration Extensions
Index Sub Type R/W Description
0x2002 0 U32 R/W Configure Module,
default = 0x00060000
0x2100 0 ARR:U16 — Calibration = 16
1 R Ch0 Offset
2 R Ch0 Gain
3 R Ch1 Offset
... — —
8 R Ch3 Gain
9 R External Ch0 Offset
... — —
Table 86. NI 9237 Scan List Format
Bits Field Description
31..23 Reserved —
22..18 Clock Divisor The NI 9237 divides the clock source (internal or
external) by this value and uses it as the
converters’ oversample clock. The data rate is
equal to 1/256 times this oversample clock
frequency. The final data rate must be between
391 kS/s and 52.734 kS/s. This means that while
all values from 1 to 31 are within the specified
operating range when using the 12.8 MHz internal
clock source, for external clock sources of more
than 13.5 MHz or less than 3.1 MHz the valid
divisors are limited to those that provide data rates
within the specified range.