Data Sheet(pdf)

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 2, 30 July 2012
PLT / PLR
NBFM Multi channel Data Packet Link Radios
Inexperienced users of ISM band radio modules often
require a totally transparent interface. This can require
considerable processing power, and buffer memory,
to be provided in the radio device.
The more experienced user, on the other hand, may
not want to write a raw radio interface, but desires a
module that gives more control over the datastream
than a 'beginners' solution.
The PL radios represent such a compromise solution.
Features
Figure 1: PLT2 transmitter and PLR2 receiver
Conforms to EN 300 220-3 and EN 301 489-3
High performance double superhet. PLL synthesizer with TCXO
SAW front-end filter
User interface speed: 9600bps for standard module
Usable range over 1km
Fully screened. Low profile
Re-programmable via RS232 interface
Low power requirements
Applications
Wireless handheld terminals
EPOS equipment, barcode scanners
Data loggers
Industrial telemetry and telecommand
In-building environmental monitoring and control
High-end security and fire alarms
DGPS systems
Vehicle data up/download
Heavy vehicle/machinery controls
Technical Summary
Operating frequency: 173.200 - 173.325MHz (UK band)
o 150.825 - 152.450MHz (Australian Band)
o 433.875 - 434.650MHz (EU band)
o 458.525 - 459.1MHz (UK band)
Other custom VHF and UHF bands
32 channels @ 25kHz channel spacing
Transmit power: +10dBm (10mW) / +20dBm (100mW)
Supply range: 3.1 – 15V (TX @ 10mW and RX), 4.1 – 15V (TX @ 100mW)
Current consumption: 34mA @ 10mW, 90mA @ 100mW (transmit) and 20mA (receive)
Data bit rate: 5kbps max. (standard module)
Receiver sensitivity: -118dBm (for 12 dB SINAD)
Serial configuration by inverted RS232 at 3V CMOS level
Evaluation platforms: NBEK + PL carrier
Radiometrix Ltd
PLT/PLR Data Sheet
page 1
PLT / PLR data packet link radios
The PL modules use the hardware of the existing LMT/LMR transmitter receiver pair, combined with
completely new firmware to produce a simple to use but readily controllable data link
Both radios have a similar pinout. The bidirectional DATA pin requires an inverted RS232 data interface, at
3V CMOS logic levels (Both DATA and FLOW are bidirectional. As outputs they are open drain pins with 50K
pullups to the internal Vcc, and 470 series protection resistors. Do not exceed 3v on these pins).
The CMD pin selects the operating mode: If pulled low, then serial data is routed to a command interpreter
(see 'programming') . If high (floating) then received bytes are loaded into the buffer (the PLR receiver only
inputs data in command mode of course).
When the buffer is full, the transmitter either sends a databurst immediately, or waits for a command from the
user
The transmitter data buffer size is pre-set by a user command (from 1-32 bytes)
The data format uses is modified biphase at a peak data rate of 2500 bits per second.
Each burst consists of a framing sequence, a two byte address, a two byte checksum, and a variable length
(1-32 bytes) data 'payload'. The payload length information is coded into the framer sequence.
Minimum length (1 byte) bursts take about 70mS (including all transmitter setup and power on/off timings),
while a full 32 byte burst requires over 250mS.
Data transfer rate is limited by the interface's inability to receive data while transmitting a burst (if FLOW is
high, then the PLT is not listening to the serial port at all), or to decode received packets while in the process
of outputting one
The standard products use a 9600 baud user interface speed. Slower versions are also available (1200,
2400 and 4800 baud, with suffixes -1, -2, and -4). The baud rate is not user programmable.
Radiometrix Ltd
PLT/PLR Data Sheet
page 2
Figure 2: PLT block diagram
Radiometrix Ltd
PLT/PLR Data Sheet
page 3
Figure 3: PLT footprint (top view)
Pin description – PLT
Pin
1a
Name
Vcc
2a
3a
4a
0V
TXE
TXD
Function
3.1 – 15V power supply (@ 10mW)
4.1 – 15V power supply (@ 100mW)
Ground
Transmit Enable (active low)
(link to 4b)
1b
2b
3b
4b
CMD
DATA
FLOW
Tout
Command mode select input
Serial data out/in
Buffer full / busy output
(link to 4a)
Notes:
1. This pinout is very similar to the LMT radios but the serial data is on pin 2b (not 1b, which is here
used as the command mode select input )
2. Serial programming is by an inverted, CMOS logic level, 9600 baud RS232 datastream applied to
the DATA pin (2b).
3. TXE has a 100kΩ pullup to Vcc
4. All pins are on an 0.1" grid
5. In the 'off' state a PIN switch open circuits the RF output pin. There are no 'off' state spuri.
6. 10mW unit will operate (with marginally reduced specifications and lower (6-8mW) output power)
from a 3.0V rail. This must be well regulated and without noise or ripple, as in this state the unit's
internal regulator no longer operates, and provides no supply rejection.
7. 100mW versions should not be run continuously from supply voltages > 9v
8. Do not exceed 3v logic levels on any input (4v for 100mW PLT units)
Application circuit
Antenna
3.1- 15V
VCC (1a)
GND (2a)
Transmit enable (active low)
TXE (3a)
TXD
1
PC serial port
TXD (4a)
6
2
3
7
4
PLT2
Vc c
(0-3V)
8
9
SGD
5
Figure 4 : Typical RS232 interface for programming and data input
Radiometrix Ltd
PLT/PLR Data Sheet
page 4
Figure 5: PLR block diagram
Radiometrix Ltd
PLT/PLR Data Sheet
page 5
Figure 6: PLR footprint (top view)
Pin description – PLR
Pin
1a
2a
3a
4a
5a
Name
Vcc
0V
RXE
RXD
N/C (AF out)
Function
3.1 – 15V power supply (@ 10mW)
Ground
Receiver Enable (active high)
(link to 4b)
700mV p-p audio. DC coupled, approx 0.8v bias
1b
2b
3b
4b
5b
CMD
DATA
FLOW
Rin
RSSI
Command mode select input
Serial data out/in
Valid data/serial output in progress
(link to 4a)
DC level between 0.5v and 2.2v. 60dB dynamic range
NOTES:
1. This pinout is very similar to the LMR radios but the serial data is on pin 2b (not 1b, which is here
used as the command mode select input )
2. Serial programming is by an inverted, CMOS logic level, 9600 baud RS232 datastream applied to
the DATA (2b) pin.
3. All pins are on an 0.1" grid
4. Unit will operate (with marginally reduced specifications) from a 3.0v rail. This must be well regulated
and without noise or ripple, as in this state the unit's internal regulator no longer operates, and
provides no supply rejection
5. Do not exceed 3v logic levels on any input
Application circuit
Antenna
3.1- 15V
(3V)
Receiver enable (active high)
NC
PLR2
RXD
TXD
2
1
PC serial port
Vc c
3
4
NC
6 Data
7
8 PGM
SW1
(0-3V)
9
SGD
5
Figure 7: Typical RS232 interface for programming input and data output
Radiometrix Ltd
PLT/PLR Data Sheet
page 6
Serial interface commands
A 9600 baud cmos level ‘inverted RS232 format’ (1 start bit, 8 data, 1or 2 stop bits, no parity) is used.
Serial data is sent to the DATA (2b) pin.
These units employs a sub-set of the programming commands used by standard LMT/LMR modules. As the
DATA pin is dedicated to serial communication only, the ‘ENABLESERIALMODE’ command used for
LMT/LMR string is NOT required.
To successfully program the unit it must be in active state (RXE high, or TXE low), and CMD must be pulled
low. Provision should be made to force the unit into this state while programming (either a jumper, or a third
pin on the programming connector, could be used). The basic units do not provide local echo, but this is a
provision on the evaluation interface boards
Commands
GOCHAN aa
LOAD aa nnnnn
SINGLE nnnnn
RVALUE rrrr
AVALUE aaaaa
BVALUE bb
SVALUE sss
MVALUE mmm
ADDR xxxxx
CHAN aa
TEST
Function
Serially select channel aa, (ch0 to ch31)
Set value of N register for channel aa, (Channels 0 to 31)
Direct override of N register value
Set value for R register
Set value for unit address
Set buffer size (01 – 32, PLT only)
Set ascii value of 'send' character
Set mode byte (0-255, PLT only)
Volatile short address
Volatile channel select
Transmitter test (carrier on, 250Hz square wave. PLT
only)
(any character sent to the unit will exit 'test' mode)
Process entry
Clear all buffers
Clear data buffer
send burst (if data buffer isn't empty)
<cr>
/
<
>
Note
Responds with OK
Responds with OK
Responds with OK
Responds with OK
Responds with OK
Responds with OK
Responds with OK
Responds with OK
No response
No response
Ascii 13
Ascii 47
Ascii 60
Ascii 62
aa = a two digit channel number from 00 to 31 (lead zero is important)
bb = buffer size from 1 to 32
(lead zero is irrelevant)
mmm = mode byte value (0-255)
(lead zero is irrelevant)
sss = ascii value of 'send' character (0-255)
(lead zero is irrelevant)
nnnnn = a synthesizer N register value, (up to 65535)
rrrrr = the synthesizer R register value, (up to 16383)
xxxxx = address
(up to 65535)
PLT =
N TX =
f RF
f Channelspacing
=
433.900 MHz
= 17356
25kHz
R=
f TCXO
f channelspacing
=
13MHz
, So R=520
25kHz
VHF PLT units have 10MHz, not 13MHz reference oscillators:
R=
f TCXO
f channelspacing
=
10 MHz
, So R=400 (for VHF PLT)
25 kHz
f RF − 21.4 MHz 433.900 MHz − 21.4
=
= 16500
f Channelspacing
25kHz
PLR =
N RX =
Note:
A pause of at least 50ms must be allowed between command strings (EEPROM programming time).
Radiometrix Ltd
PLT/PLR Data Sheet
page 7
Operating principle
On recieve, the FLOW output goes high at least 400uS (typically 480uS) before beginning of the start bit of
the first byte out
it goes low again 12uS after the end of the last byte stop-bit
This output can be polled, or used as an interrupt, to detect the arrival of a data byte (or bytes)
(tx measurements made on 32byte bursts, default mode 'send on buffer full)
On transmit, the FLOW output goes high 80uS after the end of the 32nd byte
(about 25-30mS after this point, the tx keys up and starts sending the burst)
it returns to low when the transmitter has ramped fully down
A 32 byte burst takes around 250mS to send, from first byte into tx, to last out of rx
(it's about 218mS from the start of the first byte in to the FLOW output returning low)
For a 32 byte burst, FLOW is high for about 185mS
Although such asynchronous operation is not really recommended (especially for timing-uncertain devices
like PCs, and especially when running high level languages and/or multiple applications), it is also possible
to send a 32 byte burst roughly every 225mS, for an aggregate throughput of about 140 bytes per second
(1400 baud)
(this is not the intended operating mode for the devices, but it does give an idea of the capabilities)
It would be much better (if maximum data rate was wanted) to send a (32byte) burst when the FLOW output
is low
The MODE byte
This is a value stored in EEPROM, that selects the various operating functions of the radio. Be careful. By
setting this incorrectly you can disable your radio link
Factory default (send when buffer full, clear buffer on exit from setup mode) is selected by MVALUE 0
Functions of the mode byte bits.
Bit0
Bit1
when zero the PLT will send when it's buffer is full
when zero the PLT clears the data buffer on exit from command mode
Bit2
Bit3
Bit4
Bit5
Bit6
Bit7
set:
send burst on entering command mode (if buffer has any data in it)
set:
send burst on stop-bit over-run (ie: serial pin is low for more than 1.04mS)
set:
clear data buffer on stop-bit over-run
set:
send burst on receiving the character specified by SVALUE in the datastream
set:
send burst if the gap following a character exceeds approx 4.2mS
reserved
Additionally, there are a few command mode characters that can be used :
>
<
send burst (if data is present in the buffer)
clear data buffer
Obviously:
bit 3 and bit 4 should not be set at the same time
bit 1 should be set if a command mode controlled send is used with a 'bouncy' CMD drive
(switch)
if bit 2 is set then it doesn't matter what bit 1 is doing !
Bit 6 (timeout mode) is best used with BVALUE 32 and other bits inactive
To generate a stop-bit over-run, either pull down the serial input pin for over 1.04mS (1 byte at `
9600 baud),
Or send a 00 (null, CTRL @ character ) at a slower baud rate
Radiometrix Ltd
PLT/PLR Data Sheet
page 8
Condensed specifications
Frequency
Frequency stability
Channel spacing
Number of channels
Operating temperature
Spurious radiations
Transmitter
Output power
Peak deviation
Modulation type
TX modulation bandwidth
Adjacent channel TX power
TX spurious
Supply
Voltage
Current
Inputs
Size
Interface
User
RF
Recommended PCB hole size
Receiver
Sensitivity
AF bandwidth (-3dB)
image
spurii / adjacent channel
blocking
LO re-radiation
Auxiliary outputs
Supply
Voltage
Current
Size
Interface
User
RF
Recommended PCB hole size
Radiometrix Ltd
433MHz EU, 458MHz / 173MHz UK and 151MHz Australian bands
As supplied: EU version: 433.875 - 434.65MHz
UK version: 458.525 - 459.1MHz
173.200 - 173.325MHz
Australian version: 150.825 - 152.450MHz
And other custom VHF and UHF bands
±1.5kHz
25kHz
32 (controlled via RS232 interface)
-20 ºC to +55 ºC (Storage -30 ºC to +70 ºC)
Compliant with ETSI EN 300 220-3 and EN 301 489-3
+10dBm (10mW) ±1dB (factory adjustable 1 - 25mW)
+20dBm (100mW) ±1dB (factory adjustable 25 - 100mW)
±3kHz
2.5kbps FSK (biphase) data stream
DC – 5kHz (3V CMOS compatible)
<-37dBm
<-45dBm (no output in Standby)
3.1V – 15V (1-25mW)
4.1 – 15V (25 – 100mW)
35mA @ 10mW (nominal)
65mA @ 50mW (nominal)
100mA @ 100mW (nominal)
<9µA standby (TXE high or floating)
data (CMOS/TTL compatible)
33 x 23 x 9mm (BiM sized footprint, new pinout)
10 (8) pin 0.1" pitch dual row (5+5 or 4+4) header
2pin 0.1” pitch
1.2mm
-115dBm for <0.1% data errors)
4kHz
<-60db
<-65db
- 84dB
-60dBm
RSSI, audio
3.1V – 15V
20mA receive
<1µA standby (RXE low)
46 x 23 x 9mm
10 pin 0.1" pitch dual row (5+5) header
2pin 0.1” pitch
1.2mm
PLT/PLR Data Sheet
page 9
RX Received Signal Strength Indicator (RSSI)
The PLR receiver 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.
RSSI output (V)
The output on pin 5b 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 40kΩ. Pin 5b can drive a 100µA meter directly,
for simple monitoring.
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 8: typical RSSI level with respect to received RF level at PLR antenna pin
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.
Feature
Ultimate performance
Easy of design set-up
Size
Immunity proximity effects
Range open ground to similar antenna
Radiometrix Ltd
A
whip
***
***
*
*
500m
B
helical
**
**
***
**
200
PLT/PLR Data Sheet
C
loop
*
*
**
***
100
page 10
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 9: Antenna types (for 433MHz) band)
Ordering Information:
Part No.
VHF
PLT1-173-9
PLR1-173-9
PLT1-151-9
PLR1-151-9
Description
Frequency band (MHz)
Supply (V)
RF power (mW)
Transmitter
Receiver
Transmitter
Receiver
173.200 - 173.325
173.200 - 173.325
150.825 - 152.450
150.825 - 152.450
3.1 -15
3.1 -15
4.1 -15
3.1 -15
10
UHF
PLT2-433-9
PLR2-433-9
PLT2-458-9
PLR2-458-9
Transmitter
Receiver
Transmitter
Receiver
433.875-434.650
433.875-434.650
458.525 - 459.1
458.525 - 459.1
3.1 -15
3.1 -15
4.1 -15
3.1 -15
10
100
100
Data rate
9600bps
9600bps
9600bps
9600bps
9600bps
9600bps
9600bps
9600bps
9600bps
Notes:
1. The standard products use a 9600 baud user interface speed. Slower versions are also available
(1200, 2400 and 4800 baud, with suffixes -1, -2, and -4). e.g.: PLT1-173-4 (for 4800 baud)
2. PLT/PLR are available on number of other VHF and UHF frequencies. Other UHF band frequencies
are subject to SAW filter availability. e.g. 315, 419, 429, 448, 465MHz etc
.
Radiometrix Ltd
PLT/PLR 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