Wi.232DTS User’s Manual Rev 1.
1. Document Control Steve Montgomery Created By 12/9/03 Engineering Review Marketing Review Approved Engineering Approved - Marketing Revision 1.0 1.1 Author SJM SJM Date 12/9/03 12/11/03 Description Document Created -Updated DATARATE table to include 38.4kbit/sec -Corrected 4.
2. Introduction Module Overview TRANSMITTER BASEBAND DSP ANTENNA SWITCH COMBINER UART CONTROL ANTENNA VCO PROTOCOL CONTROLLER 2.1. ANALOG IN DIGITAL I/O DATA RECEIVER LEGEND HARDWARE IN WISE Wi.232 APPLICATION SOFTWARE IN WISE WiSE MAC SERIAL INTERFACE WiSE PACKET I/O INTERFACE HAL Figure 1: Wi.232DTS Block Diagram 2.2. • • • • • • • • • Features True UART to antenna solution 16-bit CRC error checking Data encryption/encoding for PGP 152.
Table of Contents Document Control................................................................................................................. 2 Introduction ........................................................................................................................... 2 2.1. Module Overview .............................................................................................................. 2 2.2. Features ...........................................................................
3. Theory of Operation The Wi.232 module combines a state-of-the-art DTS/FSK data transceiver and a highperformance protocol controller to create a transparent UART-to-antenna wireless solution capable of direct wire replacement in any embedded application. The module is designed to interface directly to a host UART. Three signals are used to transfer data between the module and the host UART: TXD, RXD, and CTS. TXD is the data output from the module RXD is the data input to the module.
is simple and is good for PGP. If a higher level of security is required, it is recommended that the user encrypt the data with an appropriate algorithm before it is sent to the module. When a module transmits a packet, all other modules on the same channel will receive the packet, check the packet for errors, decrypt the data if necessary, and send the error free data their host UARTs for processing.
4. Application Information 4.1. Pin-out Diagram Figure 3: Pin-out diagram 4.2. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Pin Description Description Ground No connect – reserved No connect – reserved Command input – active high UART receive input UART transmit output UART clear to send output – active low No connect – reserved No connect – reserved Reserved – ISP pin Reserved – ISP pin Ground Antenna port – 50 ohm Ground Ground Ground Ground Ground VCC – 2.7 to 3.
4.3. Mechanical Drawing Wi.232DTS Preliminary © 2003 Radiotronix Inc.
4.4. Example Circuit Figure 4: Example Circuit 4.5. Power Supply Although the Wi.232DTS module is very easy to use, care must be given to the design of the power supply circuit. It is important for the power supply to be free of digital noise generated by other parts of the application circuit, such as the RS-232 converter. If noise is a problem, it can usually be eliminated by using a dedicated LDO regulator for the module and/or by separating the grounds for the module and the other circuits. 4.6.
RXD TXD 4.7. CMD is held low during power-up under normal conditions. Receive data input. Transmit data output In Out Operating Mode The operating mode of the module is determined by the settings of the regMODE register. R/W SB4 7 R/W SB3 6 R/W SB2 5 R/W SB1 4 R/W SB0 3 R/W MODE 2 R/W STBY1 1 R/W STBY0 0 Bit 0-1: STBY: Standby Mode Select These bit controls the standby mode of the module. 00: The module is in sleep mode 01: The module is in active standby mode.
4.7.2. Low power Mode In low-power mode, the module is configured as follows: TX Power Deviation TX Current RX Current RX Bandwidth +0dBm +/-50kHz 41mA 22mA 200kHz 4.7.3. Active state operation When the module is in DTS or low-power mode, it is active. The primary active state is the IDLE state. When the module is not actively transmitting or receiving data, it is in this state. While in this state, the receiver is enabled and the module is continuously listening for incoming data.
4.7.4. Active Standby Mode In active standby mode, the module spends most of its time in sleep mode. The sleep time is programmed as a function of the minimum on time, which is a function of the data rate and state timing of the transceiver. Minimum On Time (mS) 16.0000 14.0000 12.0000 10.0000 Series1 8.0000 6.0000 4.0000 2.0000 0.
Duty Cycle (X:1) 10 25 50 100 150 200 300 400 500 600 700 800 900 1000 Sleep Time (mSec) 41 103 206 412 617 823 1235 1646 2058 2469 2881 3292 3704 4115 Istby (mA) 0.789 0.346 0.187 0.105 0.077 0.063 0.049 0.042 0.038 0.035 0.033 0.032 0.030 0.029 Latency (mSec) 45 107 210 416 621 827 1239 1650 2062 2473 2885 3296 3708 4119 Active standby mode introduces latency.
Most people think that frequency hopping spread spectrum and direct-sequence spread spectrum are used because the technique itself improves performance in the presence of interference. In fact, neither of these techniques is effective at combating multi-path and is only marginally effective at combating in-channel interference. The only reason that the techniques are used, in most cases, is to allow the use of higher output power, which does effectively combat both types of interference.
Baudrate 1200 4800 9600 14400 28800 38400 57600 115200 Setting 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08 TROUBLSHOOING HINT: Baud Rate Problems. If you lose track of the baud rate setting of the module, it will be impossible to program the module. You can either try every possible baud rate to discover the setting, or force a power-on reset with CMD held high to set the baud rate to its default: 38.4kbit/second. 4.11.
The transmit timeout is programmable to allow the module to work efficiently in applications where the maximum transmit packet size is less than the buffer size, which is 64 bytes. The correct value for regTXTO can be calculated by: regTXTO = ( Nbyte + 2) * 8 *1000 DRuart 4.13. Data Encoding R/W RES 7 R/W RES 6 R/W RES 5 R/W RES 4 R/W RES 3 R/W RES 2 regOPTIONS (0x66) R/W R/W RES ENC 1 0 If bit 0 is set to a 1, the data will be encrypted using the key found in regCRYPT0:regCRYPT7.
Byte 0 – Sync Byte 7 6 5 4 3 2 Byte 1 – Register Number 1 0 0xFF 7 6 5 4 3 2 1 Register Number 1 0 Byte 2 – Value to be written 7 6 5 4 3 2 1 0 Register Value (write only) The module will respond to this command with an ACK (0x06). If an ACK is not received, the command should be resent. If a write is attempted to a read-only register, the module will respond with a NAK.
Name regTXCHANNEL regRXCHANNEL regMODE regDATARATE regRFDATARATE regTXTO Name regMAC0 regMAC1 regMAC2 regOUI0 regOUI1 regOUI2 Name regOPTIONS regCRYPT0 regCRYPT1 regCRYPT2 regCRYPT3 regCRYPT4 regCRYPT5 regCRYPT6 regCRYPT7 RegQOS Non-volatile Read/Write Registers Description Transmit channel setting Receive channel setting Operating mode settings UART data rate RF data rate Transmit wait timeout Non-volatile Read Only Registers Address Description 0x32 These registers form the unique 48-bit MAC address.
5. Electrical Specifications 5.1. Absolute Maximum Ratings Parameter VCC – Power Supply Voltage on any pin Input RF Level Storage Temperature Operating Temperature 5.2. Min Max Units -0.3 -0.3 5.0 5.2 10 150 70 VDC VDC dBm °C °C -50 0 Detailed Electrical Specifications 5.2.1. AC Specifications – RX Parameter Receive frequency - US Min Typ. 902.2 Max Units Notes 927.
5.2.2. AC Specifications – TX Parameter Min Transmit Frequency -US Typ. 902.2 Center frequency error 2 Max Units 927.8 MHz 3 ppm Frequency Deviation – DTS Mode +/-235 kHz Frequency Deviation – LP Mode +/-50 kHz Output Power 0 2 Notes 915 MHz @ 25°C dBm 915 MHz Into 50 ohm load Output Power 12 14 dBm 915 MHz Into 50 ohm load Output Impedance 50 Ohms Carrier phase noise TBD dBc Into 50 ohm load Harmonic Output -50 dBc Into 50 ohm load 5.2.3.
7. Ordering Information Wi.232DTS modules can be ordered on-line 24/7 from Mouser Electronics at www.mouser.com/radiotronix. 8. Contact Us 8.1. Technical Support Radiotronix has built a solid technical support infrastructure so that you can get answers to your questions when you need them. Our primary technical support tools is the support forum and knowledge base found on our website. We are continuously updating these tools.
