Product Specs

TPRMTPRM ProductSpec.doc Proprietary Information Tellus Technology, Inc.
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RSSI:
The RSSI has a gain of  +19.6 mV/dBm
The RSSI is set at an RF Input = -100 dBm  1.35 V. This value is calibrated at the
factory and the offset value of 1.35 V at –100 dBm is not specified, nor guaranteed.
The output should be terminated into a high impedance input > 50K.
3. Software Interface
The signaling between the module and the Host is provided in the following documents:
• AT Commands ref DOC ATC
• Tellus Binary Interface Protocol ref DOC TBIP
4. Operation Procedures
This section describes a number of procedures that the Host should follow to inter-
operate properly with the modem. The procedures defined in this section are not the only
approaches for the implementation. It is prepared to help the system integrator get some
insights into the modem operations.
1.1 Protocol Synchronization
Upon power up, the Host processor should try to synchronize with the CDPD modem so
that data and commands can be exchanged reliably. The following procedure needs to
be followed to ensure the synchronization:
Initialize the parameters in the Host control processor after the overall system
initialization. Send the NULL packet (0xA3,01,A3) until receiving a response
(0xA3,41,A3) from the modem.
1.2 Modem Configuration
Before the modem can interconnect with the network, some system parameters need to
be programmed into the modem.
First of all, the Host needs to set the correct IP address in the modem. Optional settings
like SPNI, and Side Preference can also be set before connecting the modem to the
network.
1.3 Modem Connection Procedure
After the synchronization, a connection command should be issued. When the modem is
connected to the network, the Host can start sending and receiving data. Since CDPD is
a packet data system, the modem does not need to be disconnected when not in use.