Hartcran House, 231 Kenton Lane, Harrow, Middlesex, HA3 8RP, England Tel: +44 (0) 20 8909 9595, Fax: +44 (0) 20 8909 2233, www.radiometrix.com USX2 Issue 1, 07 May 2009 NBFM Multi-channel UHF Transceiver USX2 is small multi-channel half duplex UHF transceiver available for operation on 315MHz, 433MHz and 458MHz bands with the user programmable RF power output of up to 100mW. USX2 offers up to 128 frequency channels in 25kHz channel spacing. USX2 also features dual VCO which allows Figure 1: USX2-433-5 Features Conforms to ETSI EN 300 220-3 and EN 301 489-3 High performance double superhet, 128 channel PLL synthesizer 100mW RF power output: adjustable via serial command Data rates up to 5 kbps for standard module Usable range over 500m Fully screened. Low profile Feature-rich interface (RSSI, analogue and digital baseband) Digital RSSI output Incorporate a 1200baud modem Re-programmable via RS232 interface Low power requirements Applications Wireless handheld terminals Heavy vehicle/machine remote controls EPOS equipment, barcode scanners Data loggers Industrial telemetry and telecommand In-building environmental monitoring and control High-end security and fire alarms Vehicle data up/download Technical Summary Operating frequency: 315MHz (USA), 433MHz (European) and 458MHz (UK) bands 128 channels controlled via RS232 interface 16 channels selected by parallel interface Transmit power: 100mW (+20dBm) nominal. Adjustable 0.1 – 100mW Supply range: 3.6 - 15V Current consumption: 100mA (at 100mW output) transmit, 25mA receive Data bit rate: 5kbps max. (standard module) Receiver sensitivity: -118dBm (for 12 dB SINAD) Size: 50 x 30 x 12mm Radiometrix Ltd USX2 Data Sheet page 1 Figure 2: USX2 block diagram Radiometrix Ltd USX2 Data Sheet page 2 Figure 3: Provisional USX2 footprint (Top) Pin Description Pins 1A 2A 3A Normal mode RF Gnd RF ground RF in/out To the antenna RF Gnd RF ground 1 2 TXD TXE 3 4 5 6 7 8 9 GND Vcc P3 P2 P1 P0 RSSI 10 11 RXD AF out Serial mode DC coupled input for TTL/ CMOS logic Transmit enable. Low = RX mode. High = TX. (10k pull down) (0V) DC supply input (3.6 –15V) Parallel channel select MSB Parallel channel select P1 - Parallel channel select P0 - Parallel channel select LSB DC level between 0.5V and 2.5V. 60dB dynamic range Open collector output of data slicer 500mV p-p audio. DC coupled, approx 0.8V bias Modem mode NC NC Serial read back TBA TBA PGM in BUSY MOD TXD MOD RXD PGM in NC NC NOTES: 1. 2. 3. 4. 5. 6. 7. 8. No inversion occurs between TXD and RXD. However AF out is inverted relative to TXD. Parallel channel selects (P0-P3) and TXE are active LOW and have 47k internal pullups to 3V Open collector output RXD has a 47 k pullup to 3V. The software incorporates a 1200 baud modem, compatible with that implemented in other Radiometrix narrowband units ( i1200 tones and format ). Modem operation is selected by serial command. Main serial port (P0, P3) operates at 9600 baud. (Command set is not the same as TR2M, SMX families). The unit is capable of operating in 'basic' parallel channel select only mode, or in serial controlled 'expanded' mode Transmit power can be set by serial command RSSI can be read back as a digital value. (on P3) If analogue transmit modulation is needed, then connect a series 1 F cap + 500k trimmer (a multiturn is advised) in the TXD circuit. Adjust trimmer for 90% of peak deviation (+/- 2.7KHz) at mean input level. Radiometrix Ltd USX2 Data Sheet page 3 USX2 serial interface details (version 4): PRELIMINARY The USX2 user interface is accessed through the four parallel pins (P0/serial through P3). It has four operating modes: 1. Parallel: Frequency of operation is selected as one of 16 (chans 0-15), by means of a 4 bit inverted value applied to P0-P3. The P0 pin will also respond to a LOCKSERIALMODE datastream (inverted rs232, 9600 baud), which will cause the radio to enter serial mode. In parallel mode, the IDENT command string is still decoded, but the unit remains in parallel mode. 2. Serial: Frequency of operation, radio set up, power output and various other parameters are controlled by command strings sent to P0. Pin P3 functions as a 'readback' port while P1,2 are not used in this mode. In this mode, decimal values are used (to simplify direct manual programming via a terminal) Commands include : : ? or / <backspace> <cr> empty command buffer read back buffer contents delete last character process buffer PARALLEL DUMP MODEM NOMODEM return to the basic, parallel mode (and turn modem off) read back contents of eeprom (output on P3) activate 1200 baud modem # de-activate 1200 baud modem # DEFCH ccc DEFPOW pp set default channel set default tx power (non-volatile) (non-voltatile) CHAN ccc POWER pp RSSI jump to channel select tx power single read of RSSI (volatile) (volatile) (output on P3) SHORT enter short command mode # # # (The following commands are used to set up the radio operating characteristics, and should be viewed with caution. Especially the CALPOWER command, which initiates a multiple write operation to the power calibration table ) NDIV RDIV nnnnn rrrrr force N divider value force R divider value (volatile) (volatile) RLOAD rrrrr OFFSET ooooo LOAD aa nnnnn START nnnnn STEP i LIMIT ccc Set R divider value Set RX offset Set N values for first 16 channels Set N value for ch 16 Set increment for table Set highest permitted channel number SETPOW eee CALPOWER (etc) Set maximum power output (100mW) (see factory procedures for more details) TEST Generate a 250Hz test modulation (only fuctions in TX mode, cancelled by sending a <cr> byte) IDENT Readback a single byte, depending on current mode: Parallel: P Serial S Short 1 Modem M # # # # # # (Channels 0-15 are individually programmed by the LOAD operation. Channels 16-127 are a consecutive table, using the START value as a start point (=channel 16) and increasing the N value by STEP with each increase in channel number) Radiometrix Ltd USX2 Data Sheet page 4 ccc aa nnnnn rrrrr pp i ooooo eee = a channel number from 00 to 127 = a two digit channel number from 00 to 15 = synthesizer N register value, (up to 65535) = synthesizer R register value, (up to 16383) = power setting value (0 - 30) = table step (increments of N) (0-7) = receive mode frequency offset = power calibration figure N = channel frequency / (13MHz / R) 13MHz / R = 25KHz , so R = 520 (usually) receive offset = 21.4MHz / (13MHz / R) , so = 856 (usually) A pause of at least 50mS must be allowed after operations which result in eeprom programming operations (all except NDIV, RDIV, GOTO, PSET and RSSI). This allows the programming cycle to complete. Instructions marked ' # ' output a three byte ' OK<cr> ' sequence after sucessfully completing their eeprom programming cycles When first powered up, the unit will operate on channel and output level specified by the last CHAN and POWER instructions, irrespective of previous NDIV, RDIV, CHAN or PSET operations) 3. Short: A limited range of radio functions are controlled by sending a single byte to PO 0 - 127 128 - 159 200 201 222 select channel (volatile) select power ( = byte -128) (volatile) single read of RSSI (output on P3) single byte read, as for IDENT command reception of 16 consecutive 222 bytes returns radio to serial mode. This mode of operation is intended to provide a simple, fast, serial command mode. 4. Modem: Commands are interpreted as in SERIAL mode (and 'short' mode may be selected.) In this mode the unit operates as a simple 1200 baud packet modem, with TXD (in) on P2 and RXD (out) on P1. The N_TXE pin does not control tx switching in this mode, but rather the presence of valid data in the tx buffer initiates a transmit burst. No handshaking is provided, and the unit has a sufficient over-link data rate to transparently 'stream' continuous data. Error correction, re-transmission of corrupt packets and addressing are not provided. This mode is compatible with other Radiometrix 'i 1200' mode equipment, including the narrow band eval kit. Notes: Unlike in the RLC and TLC units, the LOCKSERIALMODE (and FAST) commands are non-volatile. Once a serial mode is selected, the unit will power up in this mode until a PARALLEL command is received. The command interpreter IS case sensitive. Use upper case. Spaces are optional (they are not decoded), provided the command line does not exceed 16 characters. When manually programming this unit we recommend setting your terminal to local echo. The 'backspace' key functions normally. All serial communications use 9600baud 'inverted RS232' 8 bit data, no parity, 1 start bit, 1 or 2 stop bits A simple 'driver' program will be made available to simplify programming of these units, if desired. RSSI read operations only function correctly if the unit is in RX mode (n_TXE pin is high or floating) Radiometrix Ltd USX2 Data Sheet page 5 Condensed specifications (All details are provisional) Frequency Frequency stability Channel spacing Number of channels Supply voltage Current Operating temperature Size Spurious radiations Interface User RF Reprogram Recommended PCB hole size 315 - 315.375MHz (US band) 433.875 - 434.650MHz (433 MHz EU band) 458.525 - 459.1MHz (458MHz UK band) ±1.5kHz 25kHz 128 channels selected via serial RS232 interface First 16 are individually programmable Next 112 are a sequential table 16 channels selected via parallel interface 3.6 -15V 45mA transmit (at 10mW output) 100mA transmit (at 100mW output) 25mA receive (or modem ‘idle’) ο ο -20 to +70 C (Storage -30 to +70 C) 50x 30 x 12 mm Compliant with ETSI EN 300 220-3 and EN 301 489-3 11 pin 0.1" pitch molex 3 pin 0.1" pitch molex 5 pin 0.1" pitch socket in top of case 1.2mm (min.) Transmitter Output power TX on switching time Modulation type TX modulation bandwidth Deviation Adjacent channel TX power TX spurii Inputs 100mW (+20dBm); Adjustable via serial command 0.1 - 100mW <50 ms FM, FSK (F1D, F3D) DC – 3kHz ±3kHz -37dBm <-40dBm Data (CMOS/TTL compatible) Receiver Sensitivity image / spurious blocking adjacent channel Outputs -118dBm for 12dB SINAD -60dB -84dB -60dB RSSI, Audio, Data Notes: 1. The data slicer cannot be depended upon for data waveform frequencies below 250Hz 2. When RX is on and a transmitter keys up, again a 50ms period is required to stabilise data output mark/space. i.e. allow at least 50ms of preamble Radiometrix Ltd USX2 Data Sheet page 6 RX Received Signal Strength Indicator (RSSI) The USX2 has wide range RSSI that measures the strength of an incoming signal over a range of 60dB or more. This allows assessment of link quality and available margin and is useful when performing range tests. The output on pin 9 of the module has a standing DC bias of up to 0.5V with no signal, rising to 2.5V at maximum indication (RF input levels of -40dBm and above). ∆Vmin-max is typically 2V and is largely independent of standing bias variations. Output impedance is 4.7kΩ. The pin has a 1nF cap to ground. Digital RSSI output In serial mode, RSSI can be read back as a digital value on pin P3. The RSSI read back command initiates a read of the analogue RSSI value (as present on pin 9) by an internal 8 bit A/D converter. This converter uses the 3.0v rail as it's reference (so an RSSI voltage of 3v will give a read back of 255, while a voltage of 0v will read back 00). RSSI output (V) Practically, the RSSI circuit produces about 0.5 - 2.5v (read back value 40 - 212) and this voltage is related (approximately) to the receiver input level by the graph below. 2.6 2.4 2.2 2 1.8 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0 -140 -130 -120 -110 -100 -90 -80 -70 -60 -50 -40 RF level (dBm) Figure 4: typical RSSI level with respect to received RF level at USX2 antenna pin The table below relate the receiver input level to the typical analogue voltage output at pin 9 and the corresponding digital RSSI value read back at pin 3 (in serial mode). RF power (dBm) No signal -120 -110 -100 -90 -80 -70 -60 -50 -40 Analogue RSSI (V) at pin 9 0.45 0.65 0.85 1.2 1.4 1.65 1.95 2.2 2.3 2.35 Digital RSSI value (on pin 3) 36 (24h) 53 (35h) 75 (4Bh) 101 (65h) 123 (7Bh) 141 (8Dh) 166 (A6h) 187 (BBh) 198 (C6h) 200 (C8h) Please note, the RSSI graph and the table values above are for indicative purposes only and is not a guarantee of actual RSSI characteristics. Radiometrix Ltd USX2 Data Sheet page 7 Antenna requirements Three types of integral antenna are recommended and approved for use with the module: A) Whip This is a wire, rod ,PCB track or combination connected directly to RF pin of the module. Optimum total length is 16.4cm (1/4 wave @ 433MHz). Keep the open circuit (hot) end well away from metal components to prevent serious de-tuning. Whips are ground plane sensitive and will benefit from internal 1/4 wave earthed radial(s) if the product is small and plastic cased B) Helical Wire coil, connected directly to RF pin, open circuit at other end. This antenna is very efficient given it’s small size (20mm x 4mm dia.). The helical is a high Q antenna, trim the wire length or expand the coil for optimum results. The helical de-tunes badly with proximity to other conductive objects. C) Loop A loop of PCB track tuned by a fixed or variable capacitor to ground at the 'hot' end and fed from RF pin at a point 20% from the ground end. Loops have high immunity to proximity detuning. The antenna choice and position directly controls the system range. Keep it clear of other metal in the system, particularly the 'hot' end. The best position by far, is sticking out the top of the product. This is often not desirable for practical/ergonomic reasons thus a compromise may need to be reached. If an internal antenna must be used, try to keep it away from other metal components, particularly large ones like transformers, batteries and PCB tracks/earth plane. The space around the antenna is as important as the antenna itself. 0.5 mm enameled copper wire close wound on 3.2 mm diameter former RF 433 MHz = 24 turns A. Helical antenna Feed point 15% to 25% of total loop length RF-GND track width = 1mm 2 C2 C3 C4 C1 4 to 10 cm inside area RF B. Loop antenna 16.4cm C. Whip antenna wire, rod, PCB-track or a combination of these three RF 433 MHz = 16.4 cm total from RF pin. Figure 5: Antenna types Radiometrix Ltd USX2 Data Sheet page 8 Radiometrix Ltd Hartcran House 231 Kenton Lane Harrow, Middlesex HA3 8RP ENGLAND Tel: +44 (0) 20 8909 9595 Fax: +44 (0) 20 8909 2233 [email protected] www.radiometrix.com Copyright notice This product data sheet is the original work and copyrighted property of Radiometrix Ltd. Reproduction in whole or in part must give clear acknowledgement to the copyright owner. Limitation of liability The information furnished by Radiometrix Ltd is believed to be accurate and reliable. Radiometrix Ltd reserves the right to make changes or improvements in the design, specification or manufacture of its subassembly products without notice. Radiometrix Ltd does not assume any liability arising from the application or use of any product or circuit described herein, nor for any infringements of patents or other rights of third parties which may result from the use of its products. This data sheet neither states nor implies warranty of any kind, including fitness for any particular application. These radio devices may be subject to radio interference and may not function as intended if interference is present. We do NOT recommend their use for life critical applications. The Intrastat commodity code for all our modules is: 8542 6000 R&TTE Directive After 7 April 2001 the manufacturer can only place finished product on the market under the provisions of the R&TTE Directive. Equipment within the scope of the R&TTE Directive may demonstrate compliance to the essential requirements specified in Article 3 of the Directive, as appropriate to the particular equipment. Further details are available on The Office of Communications (Ofcom) web site: http://stakeholders.ofcom.org.uk/spectrum/technical/rtte/ Information Requests Ofcom Riverside House 2a Southwark Bridge Road London SE1 9HA Tel: +44 (0)20 7981 3000 Fax: +44 (0)20 7981 3333 www.ofcom.org.uk European Radiocommunications Office (ERO) Peblingehus Nansensgade 19 DK 1366 Copenhagen Tel. +45 33896300 Fax +45 33896330 [email protected] www.ero.dk