User's Manual

116
Modem 34336
D = Dial line occupied
R = Ringing (R appears in same position as D.)
S = Connection secured by security handshake (S appears in same position
as D. S and D may flash alternately.)
TR = Data Terminal Ready
MR = Data Set Ready
RS = Request to Send
CS = Clear to Send
TD = Transmit Data
9600, 4800, etc. = Data speed
(idle—the Modem is off-line—or H-01, H-14, etc., may also be displayed
in the data speed position; see following text.)
TM = Test mode
ER = Error (poor signal quality)
CD = Carrier Detect
RD = Receive Data
When two modems establish a connection, they engage in an exchange
known as a handshake. While a handshake is taking place, the Modem
displays several codes ranging from H-01 to H-28 in the lower left corner
of the EIA status screen. A handshake lasts for up to 12 seconds and is
accompanied by various audible tones.
By pressing pushbutton 1 while the EIA status screen is displayed, you can
access two checksum screens, one for the Modem’s main circuit board and
one for the data pump. The checksums provide data intended for use by
servicing personnel. The checksum screens also show the software revision
levels (which are also shown on the power-on screen).
7.6.2 O THER S TATUS S CREENS
• Quality Screen. Displays the quality of the received signal carrier as
a numeric value and as a horizontal bar graph. A low numeric value
indicates good signal quality. The best possible signal quality is indicated
when the bar graph extends all the way to the right edge of the LCD.
• Line Levels Screen. Shows the preset level of the transmit signal (TX)
and the measured level of the receive signal (RX).