3Com 3C877 Инструкции по быстрому запуску - Страница 3

Просмотреть онлайн или скачать pdf Инструкции по быстрому запуску для Модем 3Com 3C877. 3Com 3C877 16 страниц. Impact isdn external digital modem

The 3Com Impact digital modem has an RS-232-C

asynchronous interface port that operates at data rates of up

to 115.2 Kbps. Some computers may need additional

hardware or driver software for reliable operation.

IBM PCs and Compatible Computers

An IBM

PC or compatible computer must have a buffered

UART (universal asynchronous receiver/transmitter) chip, called

the 16550 UART, to operate at 115 Kbps. Under Microsoft

™

Windows

, run the Microsoft Diagnostic Program (msd) at the

DOS prompt and select COM Ports within msd. The UARTs

present in your computer are listed under each COM port.

To operate at the maximum data rate, install an enhanced

16550 UART expansion card in your PC. If you have a

nonupgradable PC with a slower UART (16450 or 8250), the

3Com Impact digital modem can operate at lower data rates,

since it automatically adjusts to the PC serial COM port data

rate. The COMM.DRV driver for Windows 3.1 only allows data

rates of up to 38.4 Kbps. If you have a UART that supports

higher rates than this (for example, 16550), you must install the

™

TurboCom

enhanced driver that is provided with the digital

modem.

Motorola

68XXX-based Macintosh

systems support a

maximum asynchronous serial port data rate of 57.6 Kbps.

™

Power Macintosh

computers may operate at higher serial

port data rates.

Installing the 3Com Impact Digital Modem

Follow the appropriate procedure for installing the

3Com Impact digital modem in your computer. Refer to

Figure 1 during the installation procedure.