Address should already be set by Windows to the COM port address used by the modem (refer to Table 2-1). Change the Interrupt Request Line (IRQ) to match the IRQ on the modem. If you have set the modem to COM4/IRQ2, do not select IRQ2. You will need to set the IRQ in Control Panel to IRQ9 for Windows to recognize the modem. (In an operating system designed for 286 or better machines, IRQ 9 is equivalent (redirected) to IRQ2.)

After these settings are made, click OK. Click Restart Now. Windows can now recognize your modem.

We suggest the following communication parameters when you first use your data communication software. Consult the software manual for information on using these and other parameters/features.

38,400 bps; 8 data bits; no parity; 1 stop bit; RTS/ CTS flow control set to “on;” initialization string: AT&F

The commands used by the modem are compatible with the command set used by Intel modems. Select an “ Intel 144I Faxmodem” type in your data communications soft- ware, select a “ Generic Class 1” type in your fax software and select “ Cirrus Logic” in your Voice software.

2.4 COM Port and Interrupt Settings

If your computer is equipped with one or more serial ports, you will need to change the COM Port setting on the modem (to either COM 3 or 4), or disable the PC's built-in COM port.

An IRQ (interrupt request) is a signal generated by an I/O device that notifies the computer of incoming data. Your internal modem is capable of accessing IRQs 2, 3, 4, and 5.

I/O devices in your computer cannot share an IRQ with

another device at the same time. Since IRQs can not be shared at the same time, COM 3 is generally configured to use IRQ 5, and COM 4 to use IRQ 2. This avoids sharing of IRQs with COM 1 (IRQ4) and COM 2 (IRQ3).

To change the default COM Port or IRQ settings from COM 1/IRQ 4 to another setting, locate the Switch Block on your internal modem (Figure 2-3). Refer to Table 2-1 to configure the Switch Block to the COM Port and IRQ combination needed for your application. Any time the

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MaxTech V.32bis, V.42bis user manual COM Port and Interrupt Settings