Jaton Communicator V.90 User Manual

Page 36

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(38500 bps and up), the PC may not be fast enough and data may become
lost. In this case, a UART with data buffer is need such as NS16550A.

NVRAM

NVRAM(Non-Volatile RAM) is a device to store the DCE configuration.
Upon powering-up, the modem defaults to the configuration specified in the
NVRAM or to the factory default (if the NVRAM was not installed). DCE
configuration can be changed and stored by DTE in the NVRAM by first
setting up the current configuration and then sending an AT command
&Wn. The active profile will be lost if reset commands were issued or the
modem is not powered.

For examples:
ATZ

Resets and then configures the modem to
NVRAM user profile 0.

AT&F S0=1 &W1 &Y1 &F configures the modem to factory default

&S0=1 configure the modem to answer after
one ring
&W1 saves the active configuration to profile 1
&Y1 Configure the modem to use NVRAM user
profile 1 as the power-up defaults.

AT COMMAND SET AND S-REGISTER

The modem (DCE) operates in one of two states: command or on-line. In
each state, data and commands (including DCE response) are both transfer
through the UART. In command state, the host (DTE) communicates to the
modem through AT (stands for attention) commands and S-registers. AT
command set is the industry standard used to control the modem in
command state. S-registers are internal modem registers that DTE can
access. AT command set extended by each modem manufacture for the
control of more modem functions and capabilities. For more information,
please refer to the Chapter 5 AT Commands.

INITIALIZATION STRINGS

An Initialization string is a series of specific commands that prepares a
modem to operate with communications software. Consult with your

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