Vaisala FD12P - Manual (Page 54)

User's Guide _______________________________________________________________________
54 ______________________________________________________ M210296en-A
Indicators and Manual Controls
This section describes the alternatives of the indicators and manual
controls available in the FD12P DMX21 modem.
Indicators
The LED indicators of the DMX21 modem are listed and described in
Table 8 below.
Table 8 LED Indicators of the DMX21 Modem
LED Indicator Description
LED V16 R Ring indicator, normally off.
LED V17 ON LINE Normally lit when the S2 switch is in the UP position.
The line, however, is permanently connected by
jumper connections. The V17 LED may also be off
although the modem is online. The S2 switch in the
DOWN position switches the V17 LED off.
LeV18 CD Indicates when a carrier frequency is detected. To
make date interchange possible, the modems must
first detect the carrier frequency.
LED V19 TxD Transmitted data stream when the data is 1, the LED
is lit.
LED V20 RxD Received data stream. When the received data is 1,
the LED is lit.
Manual Controls
The manual controls and their positions are listed and described in
Table 9 below.
Table 9 Manual Controls of the DMX21 Modem
Control Position Description
UP
Line relay permanently on (recommended
position).
MIDDLE Line relay controlled by software (switched lines).
S2
DOWN Line relay permanently off.
UP
MIDDLE
Software-readable switch (recommended
position).
S1
DOWN
UP
ORIG mode permanently on.
MIDDLE ORIG/ANSWER modes under software control.
S3
DOWN ANSWER mode permanently on (normally
used).¹
¹ The ORIG mode may also be used depending on the host computer modem. When they
operate in the ORIGINATE mode, the modem of FD12 P should be set in the ANSWER
mode and vice versa.