Multi-Tech Systems BA-Series Loading Factory Defaults &F, Modem Reset Z, Unix Uucp Spoofing $SP

MultiModemBA User Guide

Loading Factory Defaults &F

The &F command provides a choice between customized configuration settings in RAM and the factory default configuration settings in ROM. The &F8 and &F9 commands define the function of the &F command.

The modem is shipped from the factory with a pre-configured set of command and S-Register default settings. This set of factory defaults can be recalled by issuing the &F command.

In addition to being able to recall the factory-installed defaults, the &F command can also recall those defaults stored under &W0.

This is done using the &F9 command. If you have stored parameters with the &W0 command and wish these settings to always be used as your defaults, you would enter &F9&W0.

To return the &F command to read factory installed defaults, enter &F8&W0. &F8 is the factory default.

Many datacomm program issue the &F command automatically- the &F9 command allows the user to select their own factory defaults. Note that the &F8/&F9 commands should be used with &W0.

Following is a summary of how the &F and Z reset commands interact with the &W command; note how the &F reset command operates differently from the Z reset command:

Previous Command	AT&F	Power-On and ATZ
AT&W1 (default)	ROM	ROM
AT&W0	ROM	NVRAM
AT&F8&W0	ROM	NVRAM
AT&F9&W0	NVRAM	NVRAM

Modem Reset Z

The Z command can be used to reset the entire Command Mode buffer and the result is the same as if you had disconnected, and then reconnected power to the modem. When an ATZ command is executed, the state of the &W command determines where the default values originate. &W0 defaults come from RAM and &W1 defaults come from ROM.

Unix UUCP Spoofing $SP

The modem can be configured in a Unix environment that employs ACK flow control as a means of monitoring data integrity. The modem can do “UUCP spoofing”, where the modem is able to generate ACKs at the DTE interface. Data is transmitted more time efficiently because the delay of waiting for data to be received, then for an ACK to be returned at the remote end, is eliminated. The $SP1 command enables UUCP spoofing and the default command $SP0 disables UUCP spoofing.

Async/Sync Mode Switching &M

This command can be used to set the on-line mode to either synchronous or asynchronous. AT&M0 will set the modem to Asynchronous mode, and all communications will be Asynchronous, in both On-line and Command modes. AT&M1 causes the modem to communicate asynchronously when in Command mode and switch to synchronous mode while on-line. The modem defaults to &M0 (asynchronous communications) on reset or power-up.

Synchronous Transmit Clock Select &X

The &X command selects the Synchronous Transmit Clock Source in conjunction with DIP-Switch #11. DIP-Switch #11 in the UP position enables External clocking. DIP-Switch #11 in the DOWN position enables Internal clocking (default position). External clocking is when the DTE provides transmit clocking to the modem on pin 24 of the RS-232C interface.

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