Terminal Adapter AT Commands & S-Registers

computer and responds to AT commands. There is no data communications link with a remote device.

Data Mode

The TA enters data mode when it makes a successful data communications link with a remote device. In data mode, the TA can send and receive data, but it does not respond to AT commands. Instead, it treats them as data, and transmits them to the remote device.

Online Command Mode

In online command mode, the TA responds to AT commands while maintaining a data communications link; however, transmission of data is suspended. To enter online command mode from data mode, type the escape sequence +++AT<cr>. To return to data mode from online command mode, type ATO<cr>.

Making a Call

Before you can place a data call, you must configure the TA for the local switch type, serial port speed, and the data type of the ISDN device you want to call.

Dialing

To dial a number using AT commands, you must first start a data communications program. In the program’s terminal mode, type ATDxxxxxxx<cr>, where xxxxxxx is the telephone number you want to dial, and <cr> is the carriage return character that is sent when you press ENTER , e.g, ATD7853500<cr>. The dial string can contain up to 80 characters.

To make it easier to read the dial string, you can use hyphens, spaces or parentheses. These characters are ignored by the TA. For example, the TA would read the following dial strings the same way:

ATD16127853500 <cr>

ATD 1-612-785-3500 <cr>

ATD 1 (612) 785-3500 <cr>

MultiModemISI Hybrid Series, ISIHP-2S/2U/4S/4U/4SD

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Multi-Tech Systems ISIHP-4SD, ISIHP-4U manual Making a Call, Data Mode, Online Command Mode, Dialing