Data Sheet

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
Issue 3, 02 August 2012
TX2M /RX2M
UHF NBFM multi channel radio modules
UK Version: TX2M-458-5/RX2M-458-5 (100mW)
European version: TX2M-433-5/RX2M-433-5 (10mW)
The TX2M transmitter and RX2M receiver
modules offer a low power, reliable data link
in an industry-standard pin out and
footprint. This makes the TX2M/RX2M pair
ideally suited to those low power
applications where existing wideband
modules have insufficient range, or where
multi-channel operation is needed. Two
versions are available, covering the 458.5459.1MHz UK band (at 100mW) and the
European 433.05-434.79MHz band.
RX2M-458-5
TX2I-458-5
Features
433MHz version conforms to EN 300 220-3 and EN 301 489-3
and 458MHz version to MPT 1329 (UK specs)
Any custom band between 420MHz and 480MHz with 5MHz (AR0) frequency range
High performance double superhet, 128 channel PLL synthesizer with TCXO
Data rates up to 5 kbps for standard module
Usable range over 1km
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: 458.5-459.1MHz or 433.05-434.79MHz
23 channels in 458MHz band (128 channels max.)
Transmit power: +20dBm (100mW) nominal
Supply range: 4.5V - 16V
Current consumption: 100mA transmit, 13mA receive
Data bit rate: 5kbps max. (standard module)
Receiver sensitivity: -118dBm (for 12 dB SINAD)
Evaluation platforms: NBEK + XX2M carrier
Radiometrix Ltd
TX2M/RX2M Data Sheet
page 1
Figure 1: TX2M block diagram
Radiometrix Ltd
TX2M/RX2M Data Sheet
page 2
Figure 2: RX2M block diagram
Radiometrix Ltd
TX2M/RX2M Data Sheet
page 3
Pin Description - TX2M
Figure 3: TX2M Footprint (Top) view
Pin
1A
2A
Name
+Vin
Gnd
Function
+4.5-16V
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
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
TX2M/RX2M Data Sheet
page 4
Pin Description - RX2M
Figure 4: RX2M Footprint (Top) view
Pin
1A
2A
Name
+Vin
Gnd
Function
+4.5-16V
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 RX2M mutes the AF and DATA 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
TX2M/RX2M Data Sheet
page 5
TX2M and RX2M 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
GOTEST
250Hz test tone modulated transmission
<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
=
433.050 MHz
= 17322
25kHz
R=
fTCXO
f channelspacing
=
13MHz
, So R=520
25kHz
f RF − 21.4 MHz 433.050 MHz − 21.4
=
= 16466
fChannelspacing
25kHz
Channel
Number
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
F max
433MHz
band
433.050
433.075
433.100
433.125
433.150
433.175
433.200
433.225
433.250
433.275
433.300
433.325
433.350
433.375
433.400
433.425
433.450
434.775
N value for TX
N value for RX
/LOAD00 17322
/LOAD01 17323
/LOAD02 17324
/LOAD03 17325
/LOAD04 17326
/LOAD05 17327
/LOAD06 17328
/LOAD07 17329
/LOAD08 17330
/LOAD09 17331
/LOAD10 17332
/LOAD11 17333
/LOAD12 17334
/LOAD13 17335
/LOAD14 17336
/LOAD15 17337
/LOADTB 17338
/LOADMX 69
/LOAD00 16466
/LOAD01 16467
/LOAD02 16468
/LOAD03 16469
/LOAD04 16470
/LOAD05 16471
/LOAD06 16472
/LOAD07 16473
/LOAD08 16474
/LOAD09 16475
/LOAD10 16476
/LOAD11 16477
/LOAD12 16478
/LOAD13 16479
/LOAD14 16480
/LOAD15 16481
/LOADTB 16482
/LOADMX 69
458MHz
band
458.525
458.550
458.575
458.600
458.625
458.650
458.675
458.700
458.725
458.750
458.775
458.800
458.825
458.850
458.875
458.900
458.925
459.100
N value for TX
N value for RX
/LOAD00 18341
/LOAD01 18342
/LOAD02 18343
/LOAD03 18344
/LOAD04 18345
/LOAD05 18346
/LOAD06 18347
/LOAD07 18348
/LOAD08 18349
/LOAD09 18350
/LOAD10 18351
/LOAD11 18352
/LOAD12 18353
/LOAD13 18354
/LOAD14 18355
/LOAD15 18356
/LOADTB 18357
/LOADMX 23
/LOAD00 17485
/LOAD01 17486
/LOAD02 17487
/LOAD03 17488
/LOAD04 17489
/LOAD05 17490
/LOAD06 17491
/LOAD07 17492
/LOAD08 17493
/LOAD09 17494
/LOAD10 17495
/LOAD11 17496
/LOAD12 17497
/LOAD13 17498
/LOAD14 17499
/LOAD15 17500
/LOADTB 17501
/LOADMX 23
Please observe the following ERC/REC 70-03 (April 2004) Annex 1 recommendation when using the Nonspecific Short Range Device (SRD) band for Telemetry, Telecommand, Alarms, Data in general and other
similar applications.
Frequency Band
ERP
Duty
Channel
Notes
Cycle
spacing
E (433.050 - 434.790MHz)
10mW
<10% No spacing Audio and voice signals should be
E1 (433.050 - 434.790MHz)
1mW <100% No spacing avoided in the band 433.050MHz 434.790MHz
E2 (434.040 - 434.790MHz)
10mW <100%
<25kHz
Power density limited to -13dBm/10
kHz for wideband channels with a
bandwidth greater than 250 kHz
Radiometrix Ltd
TX2M/RX2M Data Sheet
page 6
Set parallel frequency select mode
Go to Channel 3 (458.600MHz)
Go to Channel 13 (458.850MHz)
Go to Channel 23 (459.100MHz maximum allowed Channel)
Go to Channel 22 (459.075MHz)
TX2M will wrap around to Ch0 if >Ch23 (459.100MHz)
Increase highest channel to Ch30 (out of 458MHz band)
Go to new maximum Channel 30 (459.275MHz)
Reset the maximum Channel to regulatory band limit
Ch16 onwards changed from 458.925MHz to 459.000MHz
Go to new Ch18 frequency of 459.050MHz (not 458.975MHz)
Go to new maximum Ch23 frequency of 459.175MHz
Reset Ch16 onwards from 458.925MHz (within regulatory band)
Clear buffer and return to parallel channel selection
Clear buffer and go to last serially selected Ch23 (458.925MHz)
Return serially selected Channel to 0 (458.525MHz)
Return to channel selected by parallel pins (P1-P3) levels
Jump to 459.500MHz without storing it on EEPROM
Enable internal 1200baud modem
Enable internal 250Hz square wave modulated test transmission
Figure 5: Serial configuration of TX2I-458-5 transmitter using HyperTerminal
25kHz
433.05
434.79
433MHz Band
458MHz
Band
459.1
461.675
Figure 6: Maximum allowed and programmable channels
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
3. In 458MHz band, channel 12 (458.825MHz) and channel 15 (458.900MHz) are allocated specifically
for fixed alarm and radio keys/vehicle paging applications respectively and should not be used for
general purpose applications.
Radiometrix Ltd
TX2M/RX2M Data Sheet
page 7
Pin description of TX2M/RX2M 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 - TX2M
Pin
1
2
3
4
5
6
7
8
9
10
Name
0V
TXE
N/C
N/C
+4.4Vout
PGM
0V
MOD TXD (P1)
MOD N/C (P2)
MOD TXH (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)
Pin Description - RX2M
Pin
1
Name
RSSI
Function
DC level between 0.5V and 2.5V. 60dB dynamic range
(only valid during databursts)
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)
(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 TX2M and the RX2M 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)
TX2M
PC serial port
1
TXD
2
3
4
+4.4V out (C5)
GND (C6)
RX2M 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: TX2M and RX2M 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 TX2M, 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 RX2M, 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
TX2M/RX2M Data Sheet
page 8
Condensed specifications
Frequency
Frequency stability
Channel spacing
Number of channels
458.5-459.1MHz or 433-434MHz (any 5MHz band from 420-480MHz)
+/- 1.5kHz
25kHz (12.5kHz by special order)
128 channels controlled via RS232 interface (8 parallel selected)
Supply
4.5-16V
100mA nominal transmit
13mA receive
voltage
Current
Operating temperature
Size
Spurious radiations
Interface
user
Power
RF
Recommended PCB hole size
Intended approval
Transmitter
Output power
TX on switching time
Modulation type
TX modulation bandwidth
Adjacent channel TX power
Inputs
Receiver
Sensitivity
image / spurious
Blocking
adjacent channel
Outputs
Power on to valid audio
Power on to valid audio
Power on to stable data out
ο
ο
-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
8pin 0.1" pitch molex
2pin 0.1" pitch molex
3pin 0.1" pitch molex
1.2mm (min.)
ETSI Radio standard EN 300 220-3 and EMC standard EN 301 489-3
+20dBm(100mW) ± 1dB (factory adjustable 1 - 100mW)
50 ms
FM, FSK (F1D, F3D)
DC – 3kHz
-37dBm
analogue, data (CMOS/TTL compatible)
-112dBm for 1 part per 1000 BER
-118dBm for 12 dB SINAD
-70dB
-85dB
<-60dB (Tested per. ETSI EN 301 489-3
RSSI, carrier detect, audio, data
28ms (no noise mute)
45ms (with noise mute)
50ms for 50:50 mark / space (with or without mute)
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
Typical current consumption of TX2M at various RF output power level is as follows:
RF output (mW)
100
50
25
10
5
1
Note:
Current (mA)
90
67
54
41
35
30
These measurements taken at 433MHz (for 458MHz current consumption increases by about 5%).
RF power output can only be factory set.
Radiometrix Ltd
TX2M/RX2M Data Sheet
page 9
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 TX2M 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.
The advantage of using the above coding technique:
1.Ease of decoding:
Unlike biphase, where a bit is coded as either a long half cycle or a
short cycle, here all half cycles are detected separately.
2. Inherent error detection:
Although only 14 sync/address 'bits' (halfcycles) are used, the following
48 'bits' (halfcycles) only code 24 real data bits, leading to enhanced
noise/error discrimination (the equivalent of 5 more sync bits).
For a maximum transmitted baseband frequency of 2kHz, a 3 byte
packet is sent in 22ms. An equivalent biphase coded packet
(comprising 19 sync + 24 data + 3 null flags) at 2kbits/sec takes 23ms
3. Comparable spectral
efficiency:
Radiometrix Ltd
TX2M/RX2M Data Sheet
page 10
Transmitter variant
RX2M is designed to be pin and polarity compatible with existing industry standard modules. AF and Data
Output are inverted relative to original transmitted signal.
The transmitter is available in two variants – TX2I and TX2M
The non-inverting transmitter called TX2M 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
Data slicer
3V
RXD
RX2M
433.053MHz
433.047MHz
433.05MHz
TX2M
Figure 7: Data polarity change from TX2M (non-inverting) transmitter to RX2M receiver
The inverting transmitter called TX2I 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
0V
Data slicer
RXD
433.053MHz
433.05MHz
433.047MHz
TX2I
RX2M
Figure 8: Data polarity change from TX2I (inverting) transmitter to RX2M receiver
Ordering information
Part Number
TX2M-433-5
TX2I-433-5
RX2M-433-5
Description
TX2M (non-inverting) transmitter
TX2I (inverting) transmitter
RX2M receiver
Frequency band
433.05MHz-434.790MHz
433.05MHz-434.790MHz
433.05MHz-434.790MHz
TX2M-458-5
TX2I-458-5
RX2M-458-5
TX2M (non-inverting) transmitter
TX2I (inverting) transmitter
RX2M receiver
458.525MHz-459.100MHz
458.525MHz-459.100MHz
458.525MHz-459.100MHz
5kbps
5kbps
5kbps
TX2M-458-10 TX2M (non-inverting) transmitter
TX2I-458-10
TX2I (inverting) transmitter
RX2M-458-10 RX2M receiver
458.525MHz-459.100MHz
458.525MHz-459.100MHz
458.525MHz-459.100MHz
10kbps
10kbps
10kbps
Radiometrix Ltd
TX2M/RX2M Data Sheet
Maximum data rate
5kbps
5kbps
5kbps
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