Page 2
FCC s MPE Requirements Information to user/installer regarding FCC s Maximum Permissible Exposure (MPE) limits. Notice to users/installers using the 24 dBi parabolic dish antenna in conjunction with all Murata products. FCC rules limit the use of this antenna, when connected to Murata products for point-to-point applications only.
Page 3
5RQ Basingstoke, United Kingdom – the Notified Body having performed part or all of the conformity assessment on the product. The WIT2411 to which this declaration relates is in conformity with the essential requirements of the R&TTE directive 1999/5/EC and complies with the following standards and/or other normative documents:...
WIT2411 1. INTRODUCTION The WIT2411 radio transceiver provides reliable wireless connectivity for either point-to-point or multipoint applications. Frequency hopping spread spectrum technology ensures maximum resistance to noise and multipath fading and robustness in the presence of interfering signals, while operation in the 2.4GHz ISM band allows license-free use and worldwide compliance.
Commands for complete details on parameters affecting the transmission of data. 2.2. Data Transmission The WIT2411 supports two network configurations: point-to-point and point-to- multipoint. In a point-to-point network, one radio is set up as the base station and the other radio is set up as a remote. In a point-to-multipoint network, a star topology is used with the radio set up as a base station acting as the central communications point and all other radios in the network set up as remotes.
WIT2411 The WIT2411 has a point-to-point direct mode which fixes the remote radio’s handle at 30H. This mode is recommended for point-to-point applications, especially if the remote is likely to periodically leave and re-enter the coverage area of the base. See the section on Network Commands for details of this mode.
2.2.4. TDMA Operation In the WIT2411 TDMA scheme, the base station time slot is set independently of the remote time slots through the Set Base Slot Size command. The base divides the time remaining in the hop after subtracting for the base overhead, base slot size and guard bands between remote transmit slots into 26 equal-size remote transmit slots.
WIT2411 can still communicate reliably. Data input to the WIT2411 is broken up by the radio into packets. A 24-bit checksum is attached to each packet to verify that it was correctly received. If the packet is received...
2.3. Modes of Operation 2.3.1. Control and Data Modes The WIT2411 has two modes of operation: Control mode and Data mode. When in Control Mode, the various radio and modem parameters can be modified. When in Data Mode, only data can be transmitted. The default mode is Data Mode. There are two ways to enter Control Mode.
To compensate for the variations in nominal baud rates, the WIT2411 supports an RF flow control mode for point-to-point operation. In this mode, when the receive buffer of the receiving WIT2411 is close to full, the receiving WIT2411 stops acknowledging transmissions. The transmitting radio is set to infinite retries which invokes the RF flow control mode (See Set Packet Attempts Limit in Section 5.3).
The remotes may still use transparent mode without formatting to send data to the base, if desired. The WIT2411 protocol format is described in detail below. The protocol format is selected through the Set Protocol Mode command.
WIT2411 4. MODEM INTERFACE Electrical connection to the WIT2411 is made through a 16-pin male header on the modem module. The signals are 3.3 volt signals and form an RS-232 style asynchronous serial interface. The table below provides the connector pinout.
WIT2411 4.1. Interfacing to 5 Volt Systems The modem interface signals on the WIT2411 are 3.3 volt signals. To interface to 5 volt signals, the resistor divider network shown below must be placed between the 5 volt signal outputs and the WIT2411 signal inputs. The output voltage swing of the WIT2411 3.3 volt signals is sufficient to drive 5 volt logic inputs.
WIT2411 5. MODEM COMMANDS The WIT2411 is configured and controlled through a series of commands. These commands are sent to the modem directly when the modem is in Control Mode when the modem is in Data Mode if the escape sequence is enabled. The command syntax is the same for either method, a one- or two-letter command followed by one or more parameters.
WIT2411 5.2. Network Commands Network commands are used to set up a WIT2411 network and to set radio addressing and configuration. Command Description wb[?|0|1] Set Transceiver Mode 0 = remote (default) 1 = base station wg[?|0|1] Enable Global Network Mode (remote)
WIT2411 Set Transmit Power The WIT2411 has two preset transmit power levels, 10mW (10dBm) and 100mW (20dBm). Control of the transmit power is provided through this command. Default is 100mW. Set Point-to-Point Direct Mode Sets point-to-point mode that is recommended for point-to-point applications, especially where the remote radio is mobile and may leave and re-enter the range of the base.
Page 27
WIT2411 Set Alternative Frequency Band When set to a value between 1 and 6, will cause the WIT2411 to hop around the various 802.11b channels. When used in this mode, the WIT2411 will not interfere with co- located 802.11b systems. This mode of operation is allowed by the FCC in the United States and the ETS in Europe.
WIT2411 5.4. Status Commands These commands deal with general interface aspects of the operation of the WIT2411. Command Description zb[?|0|1] Banner Display Disable 0 = disabled 1 = enabled (default) zc[?|0..2] Set Escape Sequence Mode 0 = disabled 1 = once after reset 2 = unlimited times (default) Read factory serial number high byte.
Display Modified Parameters Recall Factory Defaults Resets the WIT2411 to its factory default state. This is useful for testing purposes or if there is a problem in operation of the system and the configuration is suspect. Use the Store Memory command afterwards if you wish the factory default settings to be remembered the next time you cycle power or reset the radio.
Connection is made to the USB port using the standard USB cable provided. The USB port is provided to simplify communicating to the WIT2411 module in the HN-511 at the 921,600 bps data rate. While most PCs can support that data rate through a USB port, they are unable to do so through a standard RS-232 port.
The fourth, Transmit Tools allows for testing of the Transparent, WIT2410/WIT910 or WIT2411 settings. Parameters related to how the transmission will take place can be set including Handle, Transmit Period, whether or not a Sequence Number should be added, if the Transmission will be continuous or one time, if the data should be sent in Hex Format and whether or not data can be received.
Can’t enter modem control mode. Make sure the host data rate is correct. The WIT2411 defaults to 9600 bps asynchronous. Evaluation units do not have external access to the CFG_SEL signal; you must use the :WIT2411 power-on escape sequence to access modem control mode.
RXD and connect ground. The HN-511 can operate with just these three wires connected. However, as the WIT2411 does not support software flow control, there will be no flow control in this mode. If the DTE device fails to respond, connect DCD from the HN-511 to the DTR and RTS inputs to activate the DTE device whenever the WIT2411 asserts carrier.
Need help?
Do you have a question about the WIT2411 and is the answer not in the manual?
Questions and answers