Справочник Пользователя для National Instruments NI 9144

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Most object dictionary entries are defined by the relevant EtherCAT and 
CANOpen specification for modular slave devices. Both the NI 9144 
device and the C Series modules have vendor extensions to the standard. 
These extensions are described here.

Most object dictionary entries are set to usable defaults during the NI 9144’s 

transition from INIT to PREOP. NI recommends writing down the object dictionary default 
values, in case you need to revert to them, before you begin to overwrite them with new 
values prior to the transition to SAFEOP.

The following lists the most common C Series module vendor extensions. Each 

module has its own extensions which may vary from the information listed here, and any 
given object dictionary index may have a different meaning depending on which module is 
inserted. For more information, refer to your C Series module documentation.

Table 3 lists common module vendor extensions.

Table 3.  Module Vendor Extensions

0x3001

0

ARR:U32

—

Timing Overrides: provides additional control over the 
timing of the NI 9144

—

1

—

R/W

Minimum free-run cycle time in nanoseconds. Set to 0 
to operate at the minimum cycle. Set to 1,000,000 for 
a 1 mS cycle (1 kHz).

—

2

—

R/W

Disables multiple scans. Setting the field to 1 disables 
multiple-scan ability. Even when a module has enough 
time during the cycle to acquire more than one set of 
data, only one acquisition occurs. This is useful when 
analyzing the module acquisition timing.

0x5FFF

0

U32

R/W

Slot address override. To address CoE requests to a 
given module’s object dictionary, write the module’s 
slot number here. Write a 0 here to cancel the slot 
address override.