1.0 Introduction
Thank you for purchasing the Land-Cellular Intelligent Modem. This guide makes
reference to the CDM819i and CDM820i modems collectively as the "modem". These
devices are CDMA2000-3G compatible and provide you with the convenience of a
wireless connection from anywhere CDMA cellular services are available. We are certain
that you will receive many years of outstanding performance from our product. This
guide will assist you in the set up and use of your new CDMA modem. Follow the
instructions below to install all necessary software/drivers and set up your computer or
data terminal to send and receive information via the cellular network.
The modem, set up as DCE in RS-232 specifications, has been designed to take
advantage of the more useful CDMA cellular network protocols such as 1xRTT and, in
the case of the Verizon carrier, DMU. The modem also supports applications which
employ a legacy v.250 (v.25ter, AT, Hayes compatible) modem interface. Typically,
these legacy applications do not support the PPP and TCP/IP transport utilized by the
digital cellular networks, but the modem is equipped to provide these protocols if the
need arises.
Internally, the modem is segregated into two major subcomponents. First, the
digital
cellular module
, which generates the Radio Frequency (RF) signal, is used to provide
connectivity to the cellular network. The second major subcomponent comes in the form
of an
onboard RISC microprocessor
which bridges the gap between your DTE
communic ations terminal and the digital cellular module. The modem’s firmware
processes the v.250 (AT) commands and other data before it is sent to the digital cellular
module. Any v.250 commands that the modems do not process internally may optionally
be passed to the digital cellular module in order to access cellular network specific
features. This provides a high level of customization for use in packet data services.
Please reference the
AT+LCPAST
command for more information on this feature.
Additionally, the device can be configured for use as standard circuit-switched cellular
data modem. In this mode, the Intelligent Modem acts as most any other land-line
modems. This mode allows compatibility with cellular networks which do not provide
CDMA packet data access.
1.1 Overview
AT commands, issued from your application, are used to control and configure the
modem. Through compatibility with the standard v.250 AT command set, these
commands can be used to control the basic functionality of the modem.
In addit ion, the modem extends the v.250 command with a set of Land Cellular
proprietary commands that can be used to configure and utilize unique features without
interfering with operation of the basic v.250 interface.
1.2 Modem Capabilities
The CDMA modem is tri-mode enabled. That is, it supports operations in AMPS
800MHz cellular, CDMA 800MHz cellular and CDMA 1900MHz PCS bands.
The modem has three operational states:
·Command State
·Online State
