User's Manual Part 2

T
2
CAS / Part No. 9000000
SYSTEM DESCRIPTION AND INSTALLATION MANUAL
34-43-20
15 Feb 2003
Use or disclosure of information on this page is subject to the restrictions in the proprietary notice of this document.
4--32
Table 4--3. 41--Pin VSI/TRA Interface Description (cont)
Connector Pin
Designation
Functional Description
J1--31 SOURCE SELECT DISCRETE INPUT (NO):
This discrete input is used in conjunction with configuration straps CS0, CS1 and CS2 to
program the VSI/TRA to accept and use the vertical speed data being supplied. In some
installations, this discrete is connected to a switch in the Flight Deck and is used to select
between primary and secondary ARINC 429 vertical speed inputs. It is hard wired to
configuration strap common if ac or dc analog vertical speed inputs are used. Cycle
power to update to the new configuration.
The following applies: O = Open, G = Ground.
CS0 CS1 CS2
Pin SS 32 33 34 Definition
X G G G ARINC 429 LS (label 212)
X O G G ARINC 565 analog AC
G G O G ARINC 575 analog DC
O G O G PNEUMATIC
X O O G ARINC 429 HS (label 365)
X G G O ARINC 429 LS (Port # 3)
X O G O Reserved (ARNICA 575 dig)
X G O O User defined
G O O O User defined
O O O O ”T raffic display only” mode
Note: SS is Source Select Pins 31 or 37.
In those configurations where digital or analog primary or secondary inputs can be
selected, the two source select pins, 31 and 37, are used to select one or other of these
inputs.
• pin 31 for the logic OPEN (primary)/GROUND (secondary)
• pin 37 for the logic OPEN (primary)/+28 Vdc (secondary) in relation to the dc common
reference pin.
Pin 31 37 Input Selected
OO Primary
G O Secondary
O 28V Secondary
G 28V Not Used
J1--32 CONFIGURATION STRAP #0 INPUT (NO):
See pin 31.
J1--33 CONFIGURATION STRAP #1 INPUT (NO):
See pin 31.