SWIT Electronics M-1090H - Manual (Page 9)

4. TALLY Light Operation
There are front TALLY lights on each of the display units, which can display RED, GREEN and YELLOW
signals. The TALLY light controlling port is the DB-9 socket at the rear panel, and terminal description is as
follows:
The RED light is on when connecting the terminal “R” with “GND”, and goes out when disconnecting.
The GREEN light is on when connecting the terminal “G” with “GND”, and goes out when disconnecting.
The YELLOW light is on when connecting the terminal “Y” with “GND”, and goes out when disconnecting.
Terminal 1 2 3 4 5 6 7 8 9
Description Y G R GND GND GND