TruTrak Digiflight II Instal Manual - Manual (Page 11)

Electrical Pin-out
All TruTrak DigiFlight II series (DigiFlight II, DigiFlight IIVS, and DigiFlight IIVSG) autopilots have consistent wiring
requirements. Therefore, this manual covers all such units, with special notations covering any differences between the units.
The table below provides a brief explanation of each pin function on the main 25-pin connector P101.
P101
Pin
Function Notes
1 Dedicated ground connection for Pitch Reverse Jumper.
Pitch Reverse Jumper,
present or absent, as follows:
Direction of servo arm / capstan rotation
(as viewed from face of the servo body)
for UP elevator
Pin 2 open (no connect): Servo CCW (counter-clockwise) Î UP
2
Pin 2 Jumper to pin 1: Servo CW (clockwise) Î UP
See note 3 on wiring
diagram
Control Wheel Switch. Connect as shown in wiring diagram to a SPST momentary switch
located remotely to the autopilot for convenient engage/disengage function.
3
Pitch Servo Torque Control. A signal from the autopilot to the pitch servo which sets the
amount of torque to be delivered by the servo. 4
Pitch Servo Trim Sensor. A signal from the pitch servo to the autopilot which indicates an
out-of-trim condition and its direction.
5
6 Autopilot Master (+12 to +28 V DC). The autopilot itself draws less than 0.5 ampere. Most of
the current required by the autopilot system is used by the servos (up to 1A per servo).
7 Auxiliary RS-232 Output. Presently unused, intended for future expansion.
8
9
10
11
Pitch Servo control lines. These lines cause the stepping motor in the pitch servo to run in the
appropriate direction at the desired velocity. They are small-signal lines and do not have any
substantial current-carrying capability or require any special shielding. Connect to pitch servo
as shown on wiring diagram.
Do NOT attempt to
reverse servo direction by
swapping wires
12 Yaw Damper option.
13 Ground Connection. Provide #20 AWG to common grounding point.
14 ARINC-A
15 ARINC-B Digital differential signals from Garmin, Sierra, or other panel-mount receiver
which provide directional steering commands (GPSS, GPSV) to autopilot Digiflight IIVSG,V Only
16 Roll Servo Torque Control. A signal from the autopilot to the roll (aileron) servo which sets
the amount of torque to be delivered by the servo.
17 Primary Serial Input. Baud rate selectable 1200, 2400, 4800 or 9600 baud. Automatically
decodes NMEA-0183, Garmin Aviation Format, or Apollo/UPSAT Moving-Map or GPSS
format. Provides directional reference to the autopilot.
18 Auxiliary RS-232 Input. Presently unused, intended for future expansion.
19 No connection
20
21
22
23
Roll (aileron) Servo control lines. These lines cause the stepping motor in the roll servo to run
in the appropriate direction at the desired velocity. They are small-signal lines and do not have
any substantial current-carrying capability or require any special shielding. Connect to roll
servo as shown on wiring diagram. Reverse servo direction if
necessary by swapping
wires on pins 20 and 21.
See note 2 on wiring
diagram.
Wiring to roll servo J201
J101 Pin 20 Pin 21
Direction of servo arm / capstan rotation
(as viewed from face of the servo body)
for RIGHT aileron
Standard J201-4 J201-5 Servo CCW (counter-clockwise) Î RIGHT
Reversed J201-5 J201-4 Servo CW (clockwise) Î RIGHT
24 No Connection. Reserved for future expansion.
25 No Connection. Reserved for future expansion.
1
20 21 22 23 24 25
2 3 4 5 6 7 8 9 10 11 12 13
14 15 16 17 18 19
Rear 25-Pin Connector P101
viewed from rear of unit
TruTrak Flight System 9 DigiFlight II Series Auto Pilot Installation Manual
December 2009 8300-008 Rev D