Z02215
Single Chip Modem with Integrated Controller, Data Pump, and AFE
29
Table 3. AT Command Set (Continued)
Function and Description
Command
\Q
Flow Control The \Q command specifies flow control between the modem and the terminal
when \N0 is selected.
Flow control prevents data from being lost by preventing the terminal from
sending data to the modem too quickly. The modem issues flow-control
characters to the terminal to inform it to stop sending data. When it is able to
receive more data by informing the terminal to resume sending data.
Similarly, the terminal can use flow control to prevent data loss caused by the
modem sending data too quickly to the terminal. Flow control does not work
unless both the terminal and the modem are configured to use the same type of
flow control.
\Q0
\Q1
This option disables flow control.
This option enables XON/XOFF flow control. In this mode,
either the modem or terminal may send an XOFF character
to stop the other device from sending data. An XON
character is sent to resume the transmission of data.
\Q2
\Q3
This option enables CTS flow control. The modem turns its
CTS signal OFF to stop data transfer. The modem turns its
CTS signal ON to permit data transfer.
This option enables RTS/CTS flow control. In this mode, the
modem uses its CTS signal as described in \Q2. The
terminal turns its RTS signal OFF to stop data transfer. The
modem turns its RTS signal ON to permit data transfer. This
value is the default value.
\Q4
This option enables unidirectional Data communication
Equipment (DCE)-to-Data Terminal Equipment (DTE) XON/
XOFF flow control. In this mode, the modem sends an
XOFF character to instruct the terminal to stop sending
data. The modem sends an XON character to instruct the
terminal to resume sending data. The modem treats XON
and XOFF characters sent from the terminal to the modem
as data characters.
#QSI
RAM
Download
Command
This command is used by a host controller to send a table of country
parameters to the modem immediately after reset. At reset, the modem uses
the country parameters stored in ROM, or the optional attached EEPROM, until
parameters are loaded into RAM using #QSI. Tables of country parameters are
created using Diplomat.
#QSIh
Download a table of parameters as ASCII hexadecimal
characters. Use this format when the host controller uses a
parity bit on data transmitted to the modem.
PS001907-0904
AT Command Set
ZILOG [ ZILOG, INC. ]
