Specifications

Chapter 19 – Host Application Scenarios
Multi-Tech Systems, Inc. CDMA C1 AT Commands Reference Guide 113
Introduction
This chapter described how to use many of the features supported by CDMA C1 devices. Earlier chapters
focused on AT command syntax and function. This chapter focuses on using the commands and how they relate
to each other.
Each scenario lists the AT commands that are used in the examples. You should be familiar with the command
descriptions before studying examples. The user scenarios are a supplement to the AT command references and
do not include all necessary details.
Note: Whether or not the unsolicited responses indicated in these scenarios appear on your device depends
on the setting of the +WUSLMSK mask.
Set Up for Serial Communication
The device's UART1 is configured as an EIA232 DCE device. Refer to the device Specifications sections in the
Developer Guide or the User Guides for more information about the UART1 configuration and pin-out.
At a minimum, the serial connection between the host processor and the CDMA-C1 device must include the
RxD, TxD and GND signals. However, We recommend that hardware flow control be used whenever possible
since it provides the best protection against serial port data overruns that could disrupt host-to-device
communications. Hardware flow control requires at a minimum that the signal lines RTS (RFR) and CTS are
connected as well.
The additional modem control lines RI, DTR, DSR and DCD are used by the device for advanced features like data
signaling, device ready indication, wakeup and online data mode. Even if you do not currently plan to use these
features, We recommend that you connect these signal lines between the host processor and the CDMA- C1
device to provide for future enhancements.
If you are using the Development Kit and your host processor or PC is configured as DTE, be sure that your serial
cable is a straight-through modem cable or DTE-DCE cable.
The UART1 default serial port settings are 115,200 bps, 8 bits, no parity, 1 stop bit and hardware flow control
enabled. These settings work well for many host applications. If you need to change UART1 settings, please refer
to the commands in the Communication Commands section. You can return the settings to their defaults by
using the AT&F command.
The remainder of the examples in this section assume that the CDMA-C1 device has been configured for
115200,n,8,1 and hardware flow control.
Acquiring Cellular Service
If your device has not been activated, refer to the Account Activation topic in the Developer Guide or User
Guide. Activation information is also online at www.multitech.com/activation.go.