Multi-Tech Systems RF300E Universal Remote User Manual


 
Appendix F - Modem AT Commands
RF300E/RF310E 175
The drawback to using this method of pacing is that some files may contain these characters as part
of the file data. If such a file is transferred using a modem with XON/XOFF flow control enabled, the
file transfer could fail due to indefinite suspension.
\Qn Local Flow Control Selection
n = 0, 1, or 3
Default: \Q3
Allows you disable flow control and enable hardware or software flow control.
\Q0 completely disables data flow control initiated by the modem. (This is the same as &K0.)
\Q1 enables XON/XOFF software flow control. XON/XOFF flow control is an in-band method of data
flow regulation. In-band data regulation means that the XON (^Q) and XOFF (^S) characters are
inserted into the stream of data rather than using separate control lines. When an XOFF character is
detected, the data stream is suspended until an XON character is detected. If you issue the &K4
command to the modem, it will respond to XON/XOFF pacing, and use XON/XOFF characters as its
own method of flow control to the computer. (This is the same as &K4.)
The drawback to using this method of pacing is that some files may contain these characters as part
of the file data. If such a file is transferred using a modem with XON/XOFF flow control enabled, the
file transfer could fail due to indefinite suspension.
\Q3 enables modem’s use of Clear to Send (CTS) signal on the RS-232/V.24 interface to regulate
data flow. When CTS drops, data flow is suspended until the signal goes high (on) again. This
method of flow control works in conjunction with pacing (i.e., computer-initiated flow control), which
uses the Request to Send (RTS) signal on the RS-232/V.24 interface. Hardware flow control cannot
be enabled unless an active error correction protocol is selected. This is the factory default setting.
(This is the same as &K3.)
\Xn XON/XOFF Pass-Through
n = 0, 1
Default: \X0
When XON/XOFF pacing is active, the local modem has two options regarding the XON and XOFF
characters. It can respond to and discard the characters from the computer, or it can respond to the
characters and pass them through the data communications link to the remote modem, thereby
pacing the remote modem as well.
\X0 causes the modem to respond to and discard the XON and XOFF characters (default)
\X1 causes the modem to respond to and pass on the XON and XOFF characters
\Jn Data Buffer Control
n = 0
Default: \J0
\J0 disables force line rate less than or equal to DTE rate
\J1 enables force line rate less than or equal to DTE rate
\Kn Set Break Control
n = 0, 1, 2, 3, 4, 5
Default: \K5
Determines how the modem processes a break signal received from the local DTE during an online
connection.
\K5 causes the modem to send the break to the remote modem in sequence with transmitted data,
non-destructive, non-expedited.