Astronics OMNIBUS II NI PXIe, Руководство пользователя

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MODULE CONFIGURATIONS
6-4 OmniBus II NI PXIe User Manual
6.3 ARINC 429 Modules
The Table 6.6 below, lists the preferred ARINC 429 I/O modules for OB2. Each
channel of those marked as R/T in the table can be configured as either a receiver
or a transmitter.
Part No. 429 Channels
Parametric
Waveform
Configurable
Frequency
Output
State
441 8 R/T

442 16 R/T

458 8R/8T
  
R = receive and T = transmit
Table 6.6—ARINC 429 Module New Applications Part Numbering
ARINC 429 modules are available in many combinations of receive/transmit
channels and features. All ARINC 429 receive channels feature automatic speed
detection and independent label and SDI filtering. Each transmit channel auto-
matically maintains accurate label repetition rates. To support data transfer pro-
tocols, the ARINC 429 module may transmit aperiodic words without altering the
timing of periodic words. Both receive and transmit channels may be
independently set for low or high speed (12.5 or 100 Kbps) and support varying
the bit rate for non-standard applications. As shown in the Table 6.7, some ARINC
429 modules provide capability to control the transmitted waveform, frequency,
and output state.
Note: When an advanced 429 transmitter is attached to a standard 429
receiver, the standard 429 receivers will clamp the bus voltage below the
200% voltage range that the advanced 429 transmitters can output. This
means you can’t connect an advanced 429 output to a standard 429 input and
get the full amplitude of the advanced 429 module.
6.3.1 Parametric Waveform
OmniBus II ARINC 429 modules with parametric waveform capability provide
control over transmit amplitude, offset and null voltages, common-mode bias, rise
time, and fall time. The amplitude, offset and null voltages are controlled by
specifying the high, null, and low voltages of the differential waveform. These
parameters can be individually set in software for each channel as shown in the
following Table 6.7.