User manual

AT COMMANDS: DATA MODEM 2-5

A/ - Repeat Last Command Line

The A/ command causes the modem to repeat the command line which is stored in

the command buffer, e.g. it will dial again, if the line is busy. This command is en-

tered without AT and no reply is issued.

➮ A command line remains until the modem receives a new command. The data

format should not be modiﬁed in the meantime.

B - BELL/CCITT Standard

The B command permits change-over between CCITT and Bell standards at 300

or 1200 bps. At 300 bps, this command will select between Bell 103 and CCITT

V.21, while at 1200 bps it will select between Bell 212A and CCITT V.22.

ATB0 CCITT V.22, V.21 (factory setting)

ATB1 Bell 212A, Bell 103

➮ The B command refers only to connections at 300 or 1200 bps. All other

speeds use the CCITT standard.

D - Automatic Dialling and Dialling Parameters

The D command instructs the modem to go on-line and to dial. If this command is

entered without parameters, the modem will go on-line in Originate mode. The

following characters are authorised in the dialling sequence: -

0 - 9 The digits of the telephone number

P, T In the Dial command, these parameters switch to pulse-dialling (P)

or to tone-dialling (T) until the other parameter is entered. The

standard setting is pulse-dialling.

W Dialling tone recognition. When this parameter is entered, the

modem will not continue dial until it has recognized the sign that

the line is free. This is an advantage in branch exchanges, where it

is not always possible to guarantee immediate access to a line.

, Dialling pause (1 sec). This comand may not be used in the dial-

ling sequence when the modem is supposed to wait for a new dial-

tone. The W-parameter must be used in this case.

A-D,*,# Additional characters when tone-dialling

S=n Dialling number which is stored with &Zn

! Call exchange by Flash

^ Switch off calling tone; this applies only during the current dial-

ling process

;H Modem as automatic dialling device. Here, the dialling sequence

is terminated by a semi-colon, followed by the H command. The

modem goes off-line after dialling and you can take over the con-

versation using a telephone. The handset must be lifted during the

dialling process.