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TT21/TT22 Transponder Installation Manual
22 August 2017
00560-00
Issue AP
______________________
Trig Avionics Limited
19
5.7.1
TC20 Interface - Pinout
Pin Signal
Direction
1
Ground
-
2
TMAPA
Bidirectional
3
TMAPB
Bidirectional
4
Altitude Out
Output
5
Reserved
Input
6
Ground
-
7
Remote ON
Output
8
Power
Input
9
Ground
-
The following diagram shows the connector orientation as viewed from the
wiring side.
5.8 TC20 Controller Interface Details
5.8.1
TMAP Bus
TMAP is a Trig proprietary bus based on RS485 signalling. It provides a bi-
directional interface between the transponder and the control head. Each
TMAP interface comprises a balanced pair of signals, called A and B, both of
which must be connected for communication to work.