Rockwell RC336D, Command Reference Manual

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Command Reference Manual
1199 3-19
3.2.2.10 &Q - Sync/Async Mode
This command is an extension of the &M command and is used to control the connection modes permitted. It is used in
conjunction with S36 and S48. (Also, see \N.)
NOTE: When the &Q0 to &Q3 command is issued to select the mode, the subsequent connect message will report the DCE
speed regardless of the W command and S95 settings.
Syntax
&Q<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0 Selects direct asynchronous operation. The value 000b is written to S27 bits 3, 1,
and 0, respectively. See &M0.
1 Selects synchronous connect mode with async off-line command mode. The value
001b is written to S27 bits 3, 1, and 0, respectively. See &M1. (Serial interface
operation only.)
2 Selects synchronous connect mode with async off-line command mode and
enables DTR dialing of directory 0. The value 010b is written to S27 bits 3, 1, and
0, respectively. See &M2. (Serial interface operation only.)
3 Selects synchronous connect mode with async off-line command mode and
enables DTR to act as Talk/Data switch. The value 011b is written to S27 bits 3, 1,
and 0, respectively. See &M3. (Serial interface operation only.)
5 The modem will try to negotiate an error-corrected link. The modem can be
configured using S36 to determine whether a failure will result in the modem
returning on-hook or will result in fallback to an asynchronous connection. The
value 101b is written to S27 bits 3, 1, and 0, respectively. (Default.)
6 Selects asynchronous operation in normal mode (speed buffering). The value 110b
is written to S27 bits 3, 1, and 0, respectively.
Result Codes
OK <value> = 0 to 3, 5, or 6.
ERROR Otherwise.
3.2.2.11 &R - RTS/CTS Option
This selects how the modem controls CTS. CTS operation is modified if hardware flow control is selected (see &K command).
The parameter value, if valid, is written to S21 bit 2.
Syntax
&R<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0 In sync mode, CTS tracks the state of RTS; the RTS-to-CTS delay is defined by
S26. In async mode, CTS is normally ON and will turn OFF only if required by flow
control.
1 In sync mode, CTS is always ON (RTS transitions are ignored). tracks the state of
RTS; In async mode, CTS is normally ON and will turn OFF only if required by flow
control.
Result Codes
OK <value> = 0 or 1.
ERROR Otherwise.