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 TX1M/RX1M Issue 3, 02 August 2012 VHF Narrow Band FM multi channel TX and RX The TX1M transmitter and RX1M receiver modules offer a low power, reliable data link in an industry-standard pin out and footprint. This makes the TX1M/RX1M pair ideally suited to those low power applications where existing wideband modules have insufficient range, or where multi-channel operation is needed in VHF frequency. Features TX1M-151-5 RX1M-151-5 Conforms to EN 300 220-3 and EN 301 489-3 Any custom band in 60 - 65MHz with 1MHz or 135 - 175MHz with 3MHz (AR0) frequency range Data rates up to 5 kbps for standard module Usable range over 1km (@100mW) Fully screened. Low profile Feature-rich interface (RSSI, automatic noise squelch, analogue and digital baseband) Incorporate a 1200baud dumb modem Re-programmable via RS232 interface Low power requirements Applications Handheld terminals 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 Size: 59 x 38 x 7mm Operating frequency: 60-65MHz or 135 – 175MHz 128 serial select or 8 parallel select channels Transmit power: +20dBm (100mW) nominal Supply range: 4.5V - 15V Current consumption: 110mA transmit, 13mA receive Data bit rate: 5kbps max. (standard module) Receiver sensitivity: -118dBm (for 12 dB SINAD) Receiver blocking -85dB Evaluation platforms: NBEK + XX2M carrier Radiometrix Ltd TX1M/RX1M Data Sheet page 1 Figure 1: TX1M block diagram Radiometrix Ltd TX1M/RX1M Data Sheet page 2 Figure 2: RX1M block diagram Radiometrix Ltd TX1M/RX1M Data Sheet page 3 Pin Description – TX1M Figure 3: TX1M Footprint (Top) view Pin 1A 2A Name Vcc Gnd Function 4.5 – 15V Ground 1B 2B 3B Gnd RF out Gnd RF ground To the antenna RF ground 1C 2C 3C 4C 0V TXE TXD AF in 5C 6C 7C 8C 9C 10C +4.4Vout PGM 0V P1 (MOD TXD) P2 (MOD NC) P3 (MOD TXH) Ground Transmitter enable. Low = ON, open = off. 4k7 internal pullup to Vcc DC coupled input for 3-12V CMOS logic. Leave open if unused AC coupled Analogue Input. Limit to 1Vpk-pk ±10% to keep distortion <1.5% and peak FM deviation >2.5kHz (>2kHz for 60-65MHz) DC supply. 75mA maximum drain. Only present when TXE is low Serial programming/configuration input at RS232 level Ground Parallel frequency select inputs. Inverted logic, 10k pullups to 4V Notes: 1. Internal AF Input gain is factory set for 1Vpk-pk to produce 3kHz peak deviation and minimum distortion. Analogue gain may be set for an input level of 50mV – 2V pk-pk. This cannot be done without appropriate test equipment. Contact factory for details 2. With 1200baud modem mode enabled, parallel selection of channel is unavailable as the P1-P3 lines are used for input/output operations. Radiometrix Ltd TX1M/RX1M Data Sheet page 4 3. Pin Description – RX1M Figure 4: RX1M Footprint (Top) view Pin 1A 2A Name Vcc Gnd Function 4.5-15V Ground 1B 2B 3B Gnd RF out Gnd RF ground To the antenna RF ground 1C 2C 3C 4C 5C 6C 7C 8C 9C 10C RSSI SQF AF out RXD +4.4V out 0V PGM P1 (MOD NC) P2 (MOD RXD) P3 (MOD CDE) DC level between 0.5V and 2.5V. 60dB dynamic range Noise operated carrier detect. Open collector. ON/low = no signal 200mVpk-pk audio. DC coupled, approx 1V bias. Muted by squelch Open collector output of data slicer. Need external pull-up DC supply. 75mA maximum drain. Present if unit is powered. Ground Serial programming/configuration input at RS232 level Parallel frequency select inputs. Inverted logic, 10K pullups to 4V Notes: 1. Carrier detect on RX1M mutes the AF and RXD outputs when RF input signal is <-123dBm. This can be factory disabled if required. 2. There are no pullups on the open collector outputs. External pull-up resistor should be used. 3. With 1200baud modem mode enabled, parallel selection of channel is unavailable as the P1-P3 lines are used for input/output operations. Radiometrix Ltd TX1M/RX1M Data Sheet page 5 TX1M and RX1M serial interface commands 2400 baud at RS232 level. 8 bit data, no parity, 1 start bit, 1 or 2 stop bits, No flow control. Transmit (pin 3 on DB9) and Signal Ground (pin 5 on DB9) should be connected to PGM and 0V pin. Command Format Description SINGLE nnnnn Set value of N for single channel operation GOCHAN xx Serial select of channel xx (0 to 127) LOADMX xx Set highest permitted (serial selected) channel xx (others default to ch0) LOADaa nnnnn Set value of N for channel aa (channels 0 to 15) LOADTB nnnnn Set value of N for channel 16 (channels 17 to 127 then in sequence) RVALUE rrrr Enter value for R register SETPAR Channel selected by 3 bit parallel input (0 to 7). Disable modem SETSER Channel selected by most recent GOCHAN operation SETMOD Enable internal modem. Frequency selected by most recent GOCHAN or SINGLE <CR> Process entry (Carriage Return = 0D hex ) / Clear all buffers xx = channel number from 00 to 127 aa = two digit channel number from 00 to 15 nnnnn = synthesizer N register value, (up to 65535) rrrr = synthesizer R register value, (up to 16383) N TX = N RX = f RF f Channelspacing = 173.250 MHz = 6930 25kHz R= fTCXO f channelspacing = 13MHz , So R=520 25kHz f RF − 21.4MHz 171.250MHz − 21.4 = = 6140 f Channelspacing 25kHz Notes: 1. A pause of at least 50ms must be allowed between command strings (EEPROM programming time) SINGLE mode does not store the N value in EEPROM. Therefore the unit is inoperative after a power down until either another valid SINGLE command is received, or mode is changed by a GOCHAN, SETPAR or SETSER command. SINGLE mode is intended for frequency agile applications. 2. /SETPAR command should be issued at the end of channel programming to put the module back into parallel frequency select mode. Radiometrix Ltd TX1M/RX1M Data Sheet page 6 Pin description of TX1M/RX1M with Modem mode selected The 'modem' mentioned is a 1200 baud RS232 semi-intelligent unit (Transmitter is enabled when valid serial data is present, so no separate Transmit Enable control is needed. Coding in the data stream also permits the receiver to ignore noise and only output valid serial data. Pin Description – TX1M Pin Name 1 0V 2 TXE 3 N/C 4 N/C 5 +4.4Vout 6 PGM 7 0V 8 MOD TXD (P1) 9 MOD N/C (P2) 10 MOD TXH (P3) Pin Description – RX1M Pin Name 1 RSSI 2 3 4 5 6 7 8 9 10 N/C N/C N/C +4.4V out 0V PGM MOD N/C (P1) MOD RXD (P2) MOD CDE (P3) Function Ground Must be tied to 0V DC supply. 75mA maximum drain. Only present when TXE is low Serial programming/configuration input at RS232 level Ground Serial data input at RS232 level Active Low Transmit Hold for continuous transmission (useful for test) Function DC level between 0.5V and 2.5V. 60dB dynamic range (only valid during databursts) (modem tones or noise present) (modem tones or noise present) DC supply. 75mA maximum drain. Present if unit is powered Ground Serial programming/configuration input at RS232 level Modem Received Data at TTL level (requires RS232 driver) Pull low to enable Carrier Detect on modem operation (not recommended) Both the TX1M and the RX1M should be configured to required operating frequency using GOCHAN command before starting to use the internal 1200 baud modem, because the P1-P3 pins will be used as Modem Data pins and the modem will operate on the last serially selected channel after SETMOD command is used to enable the Modem. Antenna Antenna 0V (C1) TXE (C2) TX1M PC serial port 1 TXD 2 3 4 +4.4V out (C5) GND (C6) RX1M PGM (C7) 4.4V 0ut (C5) 2400bps 6 SW1 PGM (C6) GND(C7) 7 5 PC serial port 2400bps 100kΩ MOD TXD 100kΩ (C8) 8 9 SGD NC (C2) 1200bps MOD RXD (C9) uC UART µC UART NPN 6 1 2 7 3 8 1200bps VDD MAX232 RXD TXD 4 9 5 SGD 4.5 - 15V 4.5 - 15V Figure 5: TX1M and RX1M interfaced to PC serial port in modem mode Note: Baud rate used for Modem is half that of used for serial configuration. Attached RS232 devices should be set with the following: 1200bps, 8 Data bits, No Parity, 1/2 stop bits, no flow control For TX1M, TXD (Pin 3) of a Serial Port can be switched from PGM (Pin C6) to MOD TXD (Pin C8) with no RS232 driver in between. However, in RX1M, MOD RXD (Pin C9) requires an RS232 line driver before it can be connected to RXD (pin 2) of a serial port. Some of the RS232 line drivers can be powered from the regulated +4.4V out (Pin C5). Radiometrix Ltd TX1M/RX1M Data Sheet page 7 Condensed specifications Frequency TX1M/RX1M: any 1MHz from 60 - 65MHz TX1M: any 3MHz band from 135-175MHz RX1M: any 2MHz band from 130-180MHz Frequency stability Channel spacing Number of channels Operating temperature Size Spurious radiations Interface User Power RF Transmitter Output power TX on switching time Modulation type TX modulation bandwidth FM deviation Adjacent channel TX power Spurii Inputs Supply Voltage Current +/- 1.5kHz 25kHz (12.5kHz by special order) 128 channels controlled via RS232 interface (8 parallel selected) º 8pin 0.1" pitch molex 2pin 0.1" pitch molex 3pin 0.1" pitch molex +20dBm(100mW) ± 1dB (factory adjustable 10 - 200mW) 50 ms FM, FSK (F1D, F3D) DC – 3kHz > ±2.5kHz (>±2kHz for 60 - 65MHz) -37dBm <-40dBm analogue, data (CMOS/TTL compatible) 4.5 - 15V @ 10mW : @ 100mW: @ 200mW: Receiver Sensitivity image / spurious Blocking adjacent channel Spurious radiations Outputs Supply Voltage Current Power on to valid audio Power on to stable data out º -10 to +60 C (Storage -30 to +70 C) 59 x 38 x 7 mm Compliant with ETSI EN 300 220-3 and EN 301 489-3 50mA 110mA 150mA -118dBm for 12 dB SINAD (for 135-175MHz) -117dBm for 12 dB SINAD (for 60-65MHz) -70dB -85dB <-65dB (Tested per. ETSI EN 301 489-3, squelch disabled) <-60dBm RSSI, carrier detect, audio, data 4.5 - 16V 13mA 28ms (no noise mute) 45ms (with noise mute) 50ms (with or without mute) for 50:50 mark / space 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 3. For UK version the following channel assignment is supplied: Channel 0 1 2 3 4 -7 8 - 127 Radiometrix Ltd Frequency (MHz) 173.250 173.275 173.300 173.325 173.225 (only used for alarm applications) 173.325 TX1M/RX1M Data Sheet page 8 4. For Australian version the following channel assignment is supplied: Channel 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 - 65 Frequency (MHz) N vlaue 150.825 /LOAD 00 6033 150.850 /LOAD 01 6034 150.875 /LOAD 02 6035 150.900 /LOAD 036036 150.925 /LOAD 04 6037 150.950 /LOAD 05 6038 150.975 /LOAD 06 6039 151.000 /LOAD 07 6040 151.025 /LOAD 08 6041 151.050 /LOAD 09 6042 151.075 /LOAD 10 6043 151.100 /LOAD 11 6044 151.125 /LOAD 12 6045 151.150 /LOAD 13 6046 151.175 /LOAD 14 6047 151.200 /LOAD 15 6048 151.225 /LOADTB 6049 in sequence starting at CH 17 (151.250) Operating principle of internal modem This device is a simplex link handling a 1200 baud asynchronous datastream (1 start, 8data, 1stop). Buffering in the transmit end handles TX startup timing requirements, while the presence of sync codes in the transmitted bursts prevents the receiver from outputting garbage in the presence of noise. No error correction or retransmission of lost packets is supported. To operate with proper +/-12V RS232 levels an external buffer (such as a MAX232) will be needed Physically the modem code resides in the PIC microcontroller which controls the radio functions. The modem uses the internal hardware serial port of the processor. Operation: Serial interface Both transmit and receive modems implement a 32 byte software FIFO. At the transmit end this is used to allow for the TX1M transmitter start up time (about 32mS), while on receive it buffers arriving packets to the constant output data rate. All timing and data formatting tasks are handled by the software. The user need not worry about keying the transmitter before sending data: the link is entirely transparent. For transmission across the link data is formatted into packets, each comprising 3 bytes of data and a sync code. If less than 3 bytes are in the transmit end FIFO then a packet is still sent, but idle state replaces the unused bytes. When the transmit end FIFO is completely emptied, then the transmitter is keyed off . Operation: Radio interface Raw data is not fed to the radios. A coding operation in the transmit software, and decoding in the receiver, isolate the AC coupled, potentially noisy baseband radio environment from the datastream. The radio link is fed a continuous tone by the modem. As in biphase codes, information is coded by varying the duration consecutive half-cycles of this tone. In our case half cycles of 500µs (a long, or L) and 250µs (a short, or S) are used. In idle (or 'preamble') state, a sequence of Ls is sent (resembling a 1kHz tone). A packet comprises the Synchronising (or address) part : LSSSSSSSSSSSSL followed by the Data part, made up of twelve Groups (of four half cycles duration). Each Group encodes 2 data bits, so one byte is encoded by 4 Groups. Although there are 16 possible states for a four half cycle group (from SSSS to LLLL), only four of the possible states are used for valid data: All other possible group combinations (except LLLL) are void, and result in the entire packet being rejected by the receiver software as a noise artifact. Idle state tone (LLLL ....) is decoded as null data, but does not void the packet, as a packet containing less than 3 bytes still needs to be decoded. Radiometrix Ltd TX1M/RX1M Data Sheet page 9 Application circuits Antenna TXD 4 + 4.4V out (C5) PGM (C6) 6 GND(C7) 7 9 SGD P1 (C8) Parallel Channel Select 8 4.5 - 15V 4.5 - 15V P2 (C9) P3 (C10) ADC or µA meter CD Data out Parallel Channel Selec t + 4.4V 6 100nF 7 8 1 2 3 TXD 4 9 SGD 5 5 PC serial port PC serial port 1 2 3 1kΩ AF in (C4) TX1M-173-5 TXD (C3) TX RSSI (C1) SQF (C2) AF out (C3) RXD (C4) + 4.4V out (C5) GND (C6) PGM (C7) P1 (C8) P2 (C9) P3 (C10) RX1M-173-5 TXE (C2) 10kΩ 0V (C1) Transmit Enable 1kΩ Antenna Figure 6: Test circuit of TX1M and RX1M TX1M/RX1M can be configured using any PC/Laptop/PDA having a serial port and modem/terminal program. TXD (pin 3) of DB9M connector can be directly wired to PGM (pin C7) of the TX1M/RX1M and SGN (pin 5) of DB9M connector should be connected to common ground pins. The whole frequency/channel table is user reconfigurable to 128 channels within 2MHz band of supplied frequency subject to regulatory band limits. Antenna 4 SGD 7 8 9 5 Parallel Channel Selec t 1kΩ PGM (C6) GND(C7) P1 (C8) P2 (C9) 4.5 - 16V 4.5 - 15V GND (C6) PGM (C7) P1 (C8) P2 (C9) P3 (C10) P3 (C10) 1kΩ AF out (C3) RXD (C4) + 4.4V out (C5) CD Data In 10kΩ 6 TX ADC 0V (C1) SQF (C2) RX1M-173-5 TXD 2 3 Data Out TXE (C2) TXD (C3) AF in (C4) + 4.4V out (C5) TX1M-173-5 1 Host Microcontroller Transmit Enable VDD 100nF Parallel Channel Select PC serial p ort Host Microcontroller Antenna 0V (C1) 6 7 8 1 2 3 TXD 4 9 5 SGD PC serial p ort Figure 7: TX1M and RX1M interfaced to host microcontroller and serial port for configuration TX1M and RX1M can be directly interfaced to a host microcontroller which can generally be powered by the regulated +4.4V output on pin 5. Three I/O pins on the microcontroller port can be assigned to select the first 8 channels on frequency table of the appropriate band for which the module is configured by pulling the P1P3 pins low. Channel select pins of TX1M and RX1M have internal pull-up to 4V supply rail, hence channel selection operate on inverted logic. Digital Received Data Output (RXD) pin on the RX1M is an open collector output, which should be pulled-up to required voltage swing level (e.g. +4.4V or Vcc). RX1M has an automatic noise squelching function which is activated when there is not any RF signal at detectable level on the channel or if the non-coherent noise like interference level is high enough to block any weak RF signal from being received. SQF is provided as an open-collector output for monitoring which should be pulled-up to required voltage swing level. SQF output will jump to pull-up voltage level if received RF signal level at the RF In/Out pin of the module is about 3dB below the level required to produce 12dB SINAD level on demodulated AF Output signal. SQF pin can be connected to an LED to act as a Carrier Detect indicator. Pull-up resistor value should be reduced (e.g. 1kΩ) according to the current requirement to produce satisfactory brightness on the LED used. Radiometrix Ltd TX1M/RX1M Data Sheet page 10 Transmitter variant RX1M in 135-175MHz is designed to be pin and polarity compatible with existing industry standard modules. AF and Data Output are inverted relative to original transmitted signal. However, RX1M in 60-65MHz band does not invert the baseband sense. The transmitter in 135-175MHz is available in two variants – TX1I and TX1M The non-inverting transmitter called TX1M frequency modulates the carrier frequency in the normal sense whereby higher modulating voltage increases the carrier frequency and lower modulating voltage decreases the carrier frequency which results in an inverted AF and Data output on the receiver. This will be the standard module and exact plug-in replacement for existing industry standard modules. No modulation Vcc AF 0V 3V Data slicer RXD 173.253MHz 173.250MHz 173.247MHz TX1M RX1M Figure 8: Data polarity change from TX1M (non-inverting) transmitter to RX1M receiver The inverting transmitter called TX1I reverses the Frequency Modulating order whereby the higher modulating voltage decreases the carrier frequency and lower modulating voltage increases carrier frequency which results in non-inverting AF and Data output on the receiver. This variant can be used for applications where data inversion will be problematic. No modulation Vcc AF 3V Data slicer 0V RXD 173.253MHz 173.250MHz 173.247MHz TX1I RX1M Figure 9: Data polarity change from TX1I (inverting) transmitter to RX1M receiver Ordering information Part Number TX1M-xxx-5 RX1M-xxx-5 Description TX1M transmitter RX1M receiver Frequency band Where xxx is any 1MHz band from 60-65MHz Maximum data rate 5kbps 5kbps TX1M-xxx-5 TX1I-xxx-5 RX1M-xxx-5 TX1M-xxx-10 TX1I-xxx-10 RX1M-xxx-10 TX1M (non-inverting) transmitter TX1I (inverting) transmitter RX1M receiver TX1M (non-inverting) transmitter TX1I (inverting) transmitter RX1M receiver Where xxx is any 3MHz band from 135-175MHz for TX1M and any 2MHz band from 130-180MHz for RX1M 5kbps 5kbps 5kbps 10kbps 10kbps 10kbps Radiometrix Ltd TX1M/RX1M Data Sheet page 11 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://www.ofcom.org.uk/ Information Requests Ofcom Riverside House 2a Southwark Bridge Road London SE1 9HA Tel: +44 (0)300 123 3333 or 020 7981 3040 Fax: +44 (0)20 7981 3333 [email protected] European Communications Office (ECO) Peblingehus Nansensgade 19 DK 1366 Copenhagen Tel. +45 33896300 Fax +45 33896330 [email protected] www.ero.dk