User Manual

CompactRF

Operating Manual: Chapter 3 Modes of Operation 11

3. Modes of Operation

The CompactRF

modem can be easily configured to meet a wide range of

needs and applications. The module is designed such that all

communication is through one serial port (Pins 21 to 28 on the module).

This port has two functions:

1. It provides the asynchronous interface with the host equipment for data

that is sent/received on the RF channel. When operating in this fashion,

the module is said to be in data mode.

2. It is also used for configuring and programming the module. When

operating in this fashion, the module is said to be in command mode.

In addition to data mode and command mode, there is a third mode of

operation called sleep mode. The module will always be in one of these

three modes.

3.1 Data Mode

Data mode is the normal operating mode of the CompactRF. When in data

mode, the CompactRF is communicating with other CompactRF modules,

and facilitating wireless asynchronous serial communication amongst two or

more terminal devices. There are three basic elements to any CompactRF

communications network:

• One module configured as the Master

• Zero or more modules configured as Repeaters

• One or more modules configured as Slaves

The function of the Master is to provide synchronization for the entire

network, and to control the flow of data. There is always one Master per

network. The Master is the ultimate destination for all data collected at the

various Repeater’s and Slave’s serial ports. With the network set up for

Point-to-Multipoint communication, all data received at the Master’s serial

port is transmitted to every Repeater and Slave in the network. The

CompactRF is a frequency hopping transceiver, meaning that it “hops” to a

new frequency after a predetermined time interval. This time interval is a

fixed time set by the user, and can range from 14ms to 180ms. The

CompactRF hops according to a pseudorandom pattern of 50 different

channels.