Intel Intel Confidential, Data Mode AT COMMANDS, 536EX Chipset Developer’s Manual, <carrier>

Data Mode AT COMMANDS

Table 18. Data Mode Command Descriptions (Continued)

Command Default Description

Modulation Selection: This command sets the preferred modulation, whether alternative modulations can be tried, and the transmit and receive DCE bit rates.

m = <carrier>,<automode>,<min rate>,<max rate>,<min rx rate>, <max rx rate>

Defaults: m = V92,1,0,0,0,0

+MS? will display the current +MS parameter settings

+MS=? will display the +MS parameter settings supported by the modem

<carrier> specifies the preferred modulation. The following table contains the modulations supported.

	<carrier>	Description
	BELL103	Bell 103 300bps (FSK)
	BELL212	Bell 212A (DPSK)
	V21	V.21	300bps (FSK)
	V22	V.22	1200bps (QAM)
	V22B	V.22 bis 1200 or 2400bps (QAM)
	V23C	V.23	1200bps forward and 75bsp reverse channel (FSK)
	V32	V.32	4800 or 9600bps (QAM) or 9600bps (TCM)
	V32B	V.32 bis 4800 or 9600bps (QAM) or7200, 9600, 12000 or 14400bsp (TCM)
	V34	V.34	2400, 4800, 7200, 9600, 12000, 14400, 16800, 19200, 21600, 24000, 26400, 28800,
		31200 or 33600bps
	V90	V.90 4800, 7200, 9600, 12000, 14400, 16800, 19200, 21600, 24000, 26400, 28800, 31200
		or 33600 bps on the transmit channel and 28000, 29333, 30666, 32000, 33333, 34666,
		36000, 37333, 38666, 40000, 41333, 42666, 44000, 45333, 46666, 48000, 49333, 50666,
		52000, 53333, 54666 or 56000 bps (PCM) on the receive channel
	V92	V.92	24000, 25333, 26666, 28000, 29333, 30666, 32000, 33333, 34666, 36000, 37333,
		38666, 40000, 41333, 42666, 44000, 45333, 46666 and 48000 bps on the transmit channel
+MS=m	see ‘m’	and 28000, 29333, 30667, 32000, 33333, 34667, 36000, 37333, 38667, 40000, 41333,
		42667, 44000, 45333, 46667, 48000, 49333, 50667,52000, 53333, 54667 or 56000 bps
		(PCM) on the receive channel

<automode> enables or disable automatic modulation negotiation. Automatic modulation negotiation allows the modem to connect with an alternative modulation to the preferred modulation. Alternative to the preferred modulations are specified by the +MA command. The +MA parameters are reset to all modulations supported by the modem below the preferred modulation whenever the +MS=<carrier> changes the preferred modulation.

Range: 0, 1

Default: 1

<automode> = 0 Disable automatic modulation negotiation

<automode> = 1 Enable automatic modulation negotiation

<min rate> and <min rx rate> specifies the lowest bit rate, in decimal units of bits/s, that may be established on the DCE. If 0, they are determined by the modulation selected by <carrier>, <automode> and the +MA command. These values are reset to 0 whenever +MS=<carrier> changes the preferred modulation. <min rx rate> is only used for modulations that support unequal minimum bit rate limits for the transmit and receive channel like V.23 and V.90 and is used to specify limits for the receive channel as distinct from the transmit channel.

Range: 0 and the DCE bps given in the <carrier> description table above

Default: 0

<max rate> and <max rx rate> specifies the highest bit rate, in decimal units of bits/s, that may be established on the DCE. If 0, they are determined by the modulation selected by <carrier>. These values are reset to 0 whenever the +MS=<carrier> changes the preferred modulation. <max rx rate> is only used for modulations that support unequal maximum bit rate limits for the transmit and receive channel like V.23 and V.90 and is used to specify limits for the receive channel as distinct from the transmit channel.

Range: 0 and the DCE bps given in the <carrier> description table above

Default: 0

NOTE: An asterisk (*) denotes the factory-default setting.

536EX Chipset Developer’s Manual 53

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