TA2922 Universal Line Interface Service Manual 17
© Tait Electronics Limited March 2010
■ RX gate output control
■ TX key input control
■ all timing functions
■ audio muting
■ alarm state detection
■ generation of alarm tones
■ TX line audio source selection
■ bi-directional I/O line processing
■ real time monitoring of digital signal states, RSSI level and audio line level.
Serial input to parallel output shift register U5 is used to expand the digital output
functionality of the microcontroller.
The microcontroller is factory programmed with the option board software and
default configuration settings. The configuration settings are technician
programmable via a serial connection to a PC running the option board
programming software. See “Programming the TA2922 board with the PGM-
UIS” on page 41.