Ositech comm Trumpcard Data/Fax Modem User's Manual And Reference page 55

Examples
AT&Q0
AT&Q4
AT&Q5
AT&Q6
&Rn — RTS/CTS Option
Parameters
Default
Controls the state of the Clear To Send (/CTS) signal operation, this can
be altered if hardware flow control is enabled. (see &K command).
Examples
AT&R0
AT&R1
&Sn — DSR Option
Parameters
Default
Determines whether Data Set Ready (/DSR) operates in accordance with
EIA-232-D specification or remains ON.
Examples
AT&S0
AT&S1
User's Guide and Reference
Selects asynchronous operation in the Direct mode.
In this mode, the communications software speed
must match the telco line speed.
Selects AutoSync operation. Is used in conjunction
with communications software that is compatible
with the Hayes Synchronous Interface (HSI).
Selects error correction mode. Modem negotiates
an error-correction link. The modem can be
configured to either disconnect or fallback to a
normal asynchronous connection if the link cannot
be negotiated (refer to register S36).
&Q5 and S36=0 Same as \N2 command (no
fallback)
&Q5 and S36=1 Same as \N3 command (fallback)
Selects asynchronous operation in Normal mode
(Speed Buffering). In this mode, the communications
software speed can differ from the telco line speed.
0 or 1
0
CTS acts according to V.25bis handshake (i.e. /CTS
tracks /RTS [Request To Send])
The modem ignores /RTS;/CTS is always ON
0 or 1
0
DSR is always ON
DSR is turned ON at start of handshaking and OFF
when carrier is lost
Modem Command Reference
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