ZyXEL Communications U-336R/RE Helpful Hints for PC Computers, Saving Settings and User Profiles

Saving Settings and User Profiles

There are some cases where you may wish to save the settings you have made as the default settings that are recalled when your modem is powered up. The AT&WZ command selects the current settings as the power-on profile.

There are four profiles that can be changed by the user, and one factory default profile. The following table lists the syntax for the commands involved in storing, recalling, and viewing profile settings.

AT&Vn	Views the settings in profile (n-1); n=0 to 5; n=0
	views current settings.
AT&Wn	Stores the current settings in user profile ‘n’; n=0 to 3
ATZn	Resets the current settings with the settings in profile
	‘n’, n=0 to 4.

Profiles 0 to 3: User profiles.

Profile 4: Factory default profile.

Helpful Hints for PC Computers

Most PCs are equipped with more than one serial port. Standard cables are readily available from many suppliers. Usually, serial ports are manufactured in two forms, either with a 25-pin male jack or a 9-pin male jack. For high speed serial connections at 230.4Kbps or 460.8Kbps, use a low-capacitance cable. Also, keep the cable as short as possible.

The serial port is driven by interrupts. Every interrupt needs a certain amount of overhead processing time. Too many interrupts reduce the computer's efficiency. The UART 16450 is very commonly used in serial port devices. For every character (byte) received, it generates an interrupt. If your hardware allows it and if

24 Basic Modem Operation