Multi-Tech Systems MT2456SMI22 manual 22bis Modulation Control Commands, +MS Modulation Selection

Chapter 4 - V.22bis Commands

V.22bis Modulation Control Commands

+MS Modulation Selection

This extended-format compound parameter controls the manner of operation of the modulation capabilities in the modem. It accepts six subparameters.

Syntax

+MS=[<carrier>[,<automode>[,<min_tx_rate>[,<max_tx_rate>[,<min_rx_rate>[,<max_rx_rate>]]]]]]

Table of +MS Command Supported Rates

Modulation	<carrier>	Possible (<min_rx_rate>, <min_rx_rate>, (<min_tx_rate>),
		and <max_tx_rate>) Rates (bps)
Bell 103	B103	300
Bell 212	B212	1200 Rx/75 Tx or 75 Rx/1200 Tx
V.21	V21	300
V.22	V22	1200
V.22bis	V22B	2400 or 1200
V.23	V23C	1200

Defined Values
<carrier>	A string which specifies the preferred modem carrier to use in originating or answering a connection.
	<carrier> values are strings of up to eight characters, consisting only of numeric digits and upper case
	letters. <carrier> values for ITU standard modulations take the form: <letter><1-4 digits><other letters
	as needed>.
<automode> A numeric value which enables or disables automatic modulation negotiation (e.g., V.22bis).
	0 =	Automode disabled.
	1 =	Automode enabled. (Default)
<min_rx_rate> and <max_rx_rate>
	Numeric values which specify the lowest (<min_rx_rate>) and highest (<max_rx_rate>) rate at which
	the modem may establish a receive connection. May be used to condition distinct limits for the receive
	direction as distinct from the transmit direction. Values for this subparameter are decimal encoded, in
	units of bit/s. Actual values will be limited to possible values corresponding to the entered <carrier> and
	fall-back <carrier> as determined during operation. (Default = lowest (<min_rx_rate>) and highest
	(<max_rx_rate>) rate supported by the selected carrier.)
<min_tx_rate> and <max_tx_rate>
	Numeric values which specify the lowest (<min_tx_rate>) and highest (<max_tx_rate>) rate at which the
	modem may establish a transmit connection. Non-zero values for this subparameter are decimal
	encoded, in units of bit/s. Actual values will be limited to possible values corresponding to the entered
	<carrier> and fall-back <carrier> as determined during operation. (Default = lowest (<min_tx_rate>) and

highest (<max_tx_rate>) rate supported by the selected carrier.)

Reporting Current or Selected Values

Command: +MS?

Response: +MS:<carrier>,<automode>,<min_tx_rate>, <max_tx_rate>,<min_rx_rate>,<max_rx_rate>

Example: +MS: V22B, 1,300,2400,300,2400

For default values. This example allows maximum system flexibility to determine optimal receive and transmit rates during operation.

Reporting Supported Range of Parameter Values

Command: +MS=?

Response: +MS: (< carrier> range),(<automode> range),(<min_tx_rate> range),(<max_tx_rate> range), (<min_rx_rate> range), (<max_rx_rate> range)

Example 1: +MS:(B103,B212,V21,V22,V22B,V23C),(0,1),(300-2400),(300-2400),(300-2400),(300-2400)

Result Code

OK Valid subparameter string

ERROR Otherwise

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