Cirrus SR22 Pilot Operating Handbook page 341

Cirrus Design Section 9
SR22 Supplements
Reply Light
The reply light is the small reverse video "R" immediately below the
mode annunciation in the display window. The reply light will blink
each time the transponder replies to ground interrogations. The light
will remain on during the 18-second IDENT time interval.
IDENT Key
Pressing the IDENT button activates the Special Position Identification
(SPI) pulse for approximately 18 seconds allowing ATC to identify your
transponder return from other returns on the controller's scope. The
Reply annunciator in the display will illuminate during the SPI pulse.
Momentarily press the IDENT key when the controller requests,
"SQUAWK IDENT."
VFR Key
Pressing the VFR key sets the transponder to the pre-programmed
VFR code selected in the configuration mode (factory set to 1200).
Pressing the VFR key a second time will restore the previous
identification code.
FUNC Key
Pressing the FUNC key changes the data shown on the right side of
the display. Pressing the FUNC key a second time will cycle the
display to the next data. Displayed data includes Pressure Altitude,
Flight Time, Count Up Timer, Count Down Timer, Contrast, and
Display Brightness.
PRESSURE ALT - Displays pressure altitude in feet. An arrow to the
right of the altitude indicates that the airplane is climbing or
descending.
FLIGHT TIME - Displays the flight time. The timer receives
groundspeed from GPS1. Flight time starts when the groundspeed
reaches 35 knots on takeoff and pauses when the groundspeed
descends below 35 knots on landing.
COUNT UP TIMER - The count up timer is controlled by the START /
STOP key. Pressing the CLR key zeros the display.
P/N 13772-102 7 of 8
Original: 12-12-00