Paradyne 3800 manual of DTE Interface Configuration Options, Async/Sync Mode Async Nxt Async Sync

COMSPHERE 3800 Series Modems

Table 9-1

(1 of 7)

DTE Interface Configuration Options

Async/Sync Mode: Async

Nxt Async Sync

Asynchronous/Synchronous Mode. Determines whether the modem operates in Asynchronous mode or Synchronous mode. If the AT command set is enabled and this configuration option is set for Sync, then the modem operates in Async mode when offline.

For Async Dial and UNIX Dial, Async is the factory default. For Sync Dial and Sync Leased, Sync is the factory default.

AT commands for Async Mode are &M0, &M231, &M232, &M235, or &Q0.

AT commands for Sync Mode are &M1, &M2, &M3, &M233, &M234, &M236 or &Q1, &Q2, &Q3.

*Async DTE Rate: 19200

Nxt 19200 57600 38400 14400 12000 9600 7200 4800 2400 1200 0–300 76800 115200

Asynchronous DTE Data Rate. Identifies the asynchronous DTE’s operating rate to the modem. Data rates from 115,200 bps to 300 bps are supported.

To originate calls in 76,800 bps Sun Workstationr environments, use either DCP dialing, DTR dialing, or handset dialing. The modem does not support AT command dialing at this data rate.

To prevent losing data in 115,200 bps applications, a 16650 UART on the PC’s serial port is required, as well as a communications package which can take advantage of its 16-byte buffer. In addition, a 386 25-MHz (or faster) PC is required, and the RS-232 cable must be 6 feet or less to minimize capacitance.

NOTE: This configuration option is ignored in Async Direct mode and synchronous mode since the DTE rate always equals the VF rate.

The factory default is 19200 bps.

AT prefix determines Async DTE Rate.

#Data Bits: 8

Nxt 8 7 9(DirectMde) 6(DirectMde)

Number of Data Bits. Determines if the data length is composed of 6, 7, 8, or 9 data bits. This data length excludes start, parity, and stop bits.

8 – Sets data length to 8 data bits. This is the default for Async mode.

7 – Sets data length to 7 data bits. This is the default for Sync mode.

9(DirectMode) – Sets data length to 9 data bits. Only valid when Error Control configuration option is set to Direct Mode.

6(DirectMode) – Sets data length to 6 data bits. Only valid when Error Control configuration option is set to Direct Mode.

The factory default is 8 data bits.

NOTE: If the DTE Dialer Type configuration option is set for AT or V.25bis Async, then the total character size must equal 10 bits (see DTE Dialer configuration options group). Total character size consists of a start bit, number of data bits, parity bits, and stop bits. V.25bis Async must use 7 data bits with even parity and 1 stop bit. The total character size for Error Control mode or Buffer mode must be 10 bits or less. The total character size for Direct mode must be 11 bits or less.

AT prefix determines the async character length.

* This configuration option only appears if Async/Sync Mode is configured for Async.

9-8 September 1998 3810-A2-GB30-30