56K V.92 Data, Fax, and Voice Chipset
Programmer’s Guide Intel Confidential 33
To configure the DTE-to-modem data rate (in data on-hook command mode), change the terminal
program COM port speed selection or write the appropriate divisor latch values for a given speed
to the UART Divisor Latch registers. Then send an AT<CR> or any other valid AT command to the
modem. The modem responds with an OK at the new data rate. All commands and modem
responses that follow use the new data rate.
Note: In command mode, the modem only changes its DTE-to-modem data rate after the Divisor Latch
register values change and the DTE sends a valid AT command.
The AT commands Bn, Nn, and +MS=m and S-register S37 define which modem-to-modem data
rates are supported by the modem. The following table shows the supported modulation types.
Each modulation supports one or more data rates.
Table 3-2. Supported Modulation Types
<carrier > Description
V21 V.21 300 bps
V22 V.22 1200 bps
V22B V.22 bis 1200 and 2400 bps
V23C V.23, with constant carrier; 1200 bps forward and 75 bps reverse
V32 V.32 4800 and 9600 bps
V32B V.32 bis 7200, 9600, 12,000, and 14,400 bps
V34 V.34 asymmetrical connections: 2400, 4800, 7200, 9600, 12,000, 14,400, 16,800, 19,200,
21,600, 24,000, 26,400, and 28,800 bps
V34B V.34 extended asymmetrical connections: 2400, 4800, 7200, 9600, 12,000, 14,400,
16,800, 19,200, 21,600, 24,000, 26,400, 28,800, 31,200, and 33,600 bps
V34S V.34 symmetrical-only connections: 2400, 4800, 7200, 9600, 12,000, 14,400, 16,800,
19,200, 21,600, 24,000, 26,400, and 28,800 bps
V34BS V.34 extended symmetrical connections: 2400, 4800, 7200, 9600, 12,000, 14,400,
16,800, 19,200, 21,600, 24,000, 26,400, 28,800, 31,200, and 33,600 bps
V90
56K V.90 asymmetrical connections (transmit): 4800, 7200, 9600, 12,000, 14,400, 16,800,
19,200, 21,600, 24,000, 26,400, and 28,800, 31,200, and 33,600 bps
56K V.90 asymmetrical connections (receive): 28,000, 29,333, 30,666, 32,000, 33,333,
34,666, 36,000, 37,333, 38,666, 40,000, 41,333, 42,666, 44,000, 45,333, 46,666, 48,000,
49,333, 50,666, 52,000 53,333, 54,666, and 56,000bps
V92
56K V.92 asymmetrical connections (transmit): 24,000, 25,333, 26,666, 28,000, 29,333,
30,666, 32,000, 33,333, 34,666, 36,000, 37,333, 38,666, 40,000, 41,333, 42,666, 44,000,
45,333, 46,666, 48,000 bps
56K V92 asymmetrical connection (receive): 28,000, 29,333, 30,666, 32,000, 33,333,
34,666, 36,000, 37,333, 38,666, 40,000, 41,333, 42,666, 44,000, 45,333, 46,666, 48,000,
49,333, 50,666, 52,000, 53,333, 54,666, 56,000 bps