Z02215 Datasheet, PDF (34/74 Pages) Zilog, Inc. – Single Chip Modem with Integrated Controller, Data Pump, and Analog Front End

Z02215
Single Chip Modem with Integrated Controller, Data Pump, and AFE
28
Table 3. AT Command Set (Continued)
Command
Function and Description
&Q
Communicat The &Q command selects the terminal communication mode: asynchronous or
ions Mode synchronous. Synchronous terminal data is transmitted directly between the
Options
terminal and data pump using the data pump clock signals.
&Q0
ASYNCHRONOUS mode. This value is the default value for
North America. The \N command controls asynchronous
terminal data options.
&Q1
SYNCHRONOUS mode. This option disconnects the
modem from the line if DTR goes from ON to OFF for longer
than the time in S-register S25 after the CONNECT result
code has been sent to the terminal.
&Q2
SYNCHRONOUS mode. This option takes the telephone
line off-hook and either answers or dials when DTR goes
from OFF to ON. If S-register S0 has been set to answer
the telephone line (S0 > 0) and more than the specified
number of ring signals are received (see S-Register S1),
then the modem answers, otherwise the modem dials the
stored telephone number (see &Z). When DTR goes from
ON to OFF for longer than the time in S-register S25, the
modern disconnects from the line.
&Q3
SYNCHRONOUS mode. This option takes the telephone
line off-hook and handshakes as either an answerer or an
originator when DTR goes from OFF to ON. If S-Register
S0 has been set to answer the telephone line (S0 > 0) and
the number of signals received is greater than the value of
S0 (see S-Register S1) then the modem answers.
Otherwise, the modem originates. The modem hangs up
when DTR goes from ON to OFF for longer in time than the
value of S-register S25.
PS001907-0904
AT Command Set