Atzn (Soft Reset, Where N = 0, 1); Atdpxxxx (Voice Call, Where X = 0-9); Atf3 (Handsfree/Mute); Atf4 (Hold) - Nortel Meridian M3905 User Manual

AT dialing

ATZn (soft reset, where n = 0, 1)

This returns S0 through S49 registers and AT configurations to their default
settings. The same result applies to both case n = 0 and n = 1.
Registers S50 through S69 will be reset to their default values only upon
power-up.
The following commands are extensions to AT dialing used to support the MCA.
ATDPxxxx (voice call, where x = 0–9)
This allows you to make a voice call from your terminal. The digits, xxxx,
represent the number of the person you wish to call. S8 registers are not
applicable. For example, a comma (pause) delays by one digit, and a maximum
of 32 digits are allowed.

ATF3 (Handsfree/mute)

This allows you to mute your end of a Handsfree call, and repeat the command to
toggle back to normal Handsfree operation.

ATF4 (Hold)

This puts an active voice call on hold.

ATF5 (Select)

This takes a voice call off hold (as if you pressed its DN key).

ATH0 (hang up data call)

This releases an active data call. You must first be off-line (hit three escape
characters).

ATHP (hang up voice call)

This releases an active voice call, just as if you pressed the Release key on the
phone.

ATTSP! (transparent mode)

You can display the raw signaling messages sent between the PBX and the MCA
using this command. This mode is used by some special software applications.
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