Northern UTA220/UTA220k - Manual (Page 62)

7-2
UTA220/UTA220k
EIA-366 Dialer Operation
INTERFACE SIGNAL DEFINITIONS
Power Indication (PWI)
PWI is supplied by the dialer to indicate the dialer has power.
Call Request (CRQ)
CRQ is supplied by the DTE to request the dialer to initiate a
call. The on condition must be maintained during call
origination. If CRQ is turned off before DSC is turned on, the
call is aborted. CRQ should not be turned on if DLO is on.
DLO indicates that the data port is in use and a call cannot be
initiated.
Data Line Occupied (DLO)
DLO is sent by the dialer to indicate when the data port is in
use. Off indicates the DTE can originate a call provided that
PWI is on.
Distant Station Connected (DSC)
DSC is supplied by the dialer to indicate that a call has been
completed and that the dialer is no longer in control of the data
port. Once the dialer has relinquished control of the data port,
DSC remains on until CRQ is turned off.
Digit Signal Circuits (NB1-NB8)
The DTE presents binary data to the dialer for dialing or dialer
control purposes. Table 7-2 shows the dial digit character set
supported by the EIA-366A dialer.
Table 7-2: Dial Digit Character Set
Digit NB8 NB4 NB2 NB1
0 0 0 0 0
1 0 0 0 1
2 0 0 1 0
3 0 0 1 1
4 0 1 0 0
5 0 1 0 1
6 0 1 1 0
7 0 1 1 1
8 1 0 0 0