Northern UTA220/UTA220k - Manual (Page 58)

6-4
UTA220/UTA220k
V.25 bis Dialer Operation
After dialing, the UTA220 attempts to establish a synchronous
connection with the remote UTA220. As in other synchronous
modes, flow control and buffering are not used when V.25 bis
is enabled. When the call begins the connection sequence, the
UTA220 sends a Call Connect Indication (CNX) message.
Upon connection, the UTA220 raises the DSR pin and enters
the on-line data mode.
Examples of valid dial commands are:
CRN 12055550123
CRN 1 (205) 555-0123
CRN 9 1-205-555-0123
Responses to the dial command are:
VAL
INVCU
INVMS
INVPS
INVPV
CFI
CFIDT
CFIET
CFIRT
CFIAB
Refer to Table 2 for a description of these response messages.
Connect Incoming Calls: CIC
This command forces the UTA220 to answer an incoming call
if the port on which the call is received is configured for manual
answer (the auto-answer option is set to off). No parameters
are allowed. The DTE typically issues this command after
receiving an INC indication from the UTA220.
Responses to the CIC command are:
VAL
INV
INVMS
INVPS
INDICATION MESSAGES
Indication messages are unsolicited messages sent by the
UTA220 to indicate a special condition, such as an incoming
call. These messages are described below.
Call Connect Indication: CNX
The UTA220 sends this message to the DTE to indicate that
an incoming or outgoing call is physically connected end-to-
end. The call connection sequence is then started. The DTE
should not begin sending data until the call connection
sequence is completed, which the UTA220 indicates by raising
the DSR pin.