| |
Figure 2: RDL2 block diagram |
| |
|
Figure 3: RDL2 Footprint (Top of the unit) view
|
| |
| Pin Description
- RDL2 |
|
Pin
|
Name
|
Function
|
| 18 |
GND |
Ground |
| 17 |
Vcc |
5V regulated
power supply (4.75 - 5.25v) |
| 16 |
ENABLE |
Pull low to enable module |
| 15 |
TXE |
Pull low to transmit |
| 14 |
TXD |
Transmit Data input ( 5v
CMOS logic. No pullup) |
| 13 |
NC |
No pin |
| 12 |
RXD |
Receive Data output ( 5v
CMOS logic output) |
| 11 |
SETUP |
Pull low
to enter test/setup mode ( 5v CMOS logic. Pullup present
sometimes) |
| 10 |
GND |
Ground |
| |
|
|
| |
Note:
1. Pinout is similar to a BiM2A. On RF connector end only
pins 1,2,3 are present.
2. TXD / RXD are a direct connection to the radio hardware's
baseband signals |
| |
RF
GND Pin 1 & 3
RF Ground pin, internally connected to the module screen
and pin 8, 9, 10 and 18 (0V). This pin should be connected
to the RF return path (e.g. co-axial cable braid, main PCB
ground plane, etc). |
| |
RF
Pin 2
RF 50W RF input/output from the
antenna, it is DC isolated internally. (see antenna section
for details) |
| |
GND
Pin 8, 9, 10 and 18
Supply ground connection to ground plane and can. |
| |
Vcc
Pin 17
5V voltage regulator should be used
to have a clean 5V supply to the module. A 4V regulator
is used inside for radio circuitry. |
| |
ENABLE
Pin 16
Active low Enable pin. It has a 10kW
pull-ups to Vcc. It should be pulled Low to enable the module. |
| |
TXE
Pin 15
Active low enables transmitter.
It has a 10kW pull-up to Vcc. (if used in RX only, tie this
pin to +5v) |
| |
TXD
Pin 14
This is a 5V CMOS logic level input. It can be directly
interfaced to data output of a UART in a microcontroller.
TXD does not have an internal pull-up. |
| |
NC
Pin 13
There is no pin in this position. |
| |
RXD
Pin 12
This is a 5V CMOS logic level output. It can be directly
interfaced to data input of a UART in a microcontroller. |
| |
SETUP
Pin 11
Pull low to enter test/setup mode. This is only sampled
at power-up, and on tx>rx or rx>tx transitions. The
pullup only enables at these times. |
 |
| |
|
Condensed specifications
| Frequency |
433.925MHz - CHAN0
(default channel) |
| |
433.285MHz - CHAN1 |
| |
433.605MHz - CHAN2 |
| |
434.245MHz - CHAN3 |
| |
434.565MHz - CHAN4 |
| |
|
|
Frequency
stability
|
+/- 10kHz |
|
Channel
width
|
320kHz |
|
Number
of channels
|
1 of 5, user programmed |
|
Supply voltage
|
5V (4.75 - 5.25v) |
|
Current
|
28mA transmit |
| |
24mA receive/idle |
| Operating temperature |
-20 to +70 °C
(Storage -30 to +70 °C) |
| Size |
33 x 23 x 7mm |
| Spurious radiations |
Compliant with ETSI
EN 300 220-3 and EN 301 489-3 |
| Interfaces user |
9pin 0.1" pitch
molex (pin 6 absent) |
|
RF |
3pin 0.1" pitch
molex |
| |
|
| Transmitter
|
|
| Output power |
10dBm (10mW) +/- 1dB |
| TX on switching
time |
<5 ms |
| Modulation
type |
FSK |
| FM peak
deviation |
+/-25kHz |
| Adjacent channel TX
power |
<-37dBm |
| TX spurious |
<-45dBm |
| |
|
| Receiver |
|
| Sensitivity |
-115dBm
for 12dB SINAD, 1KHz tone, at the analogue AF test |
| image |
-40dB |
| spurious / adjacent
channel |
-60dBm |
| blocking |
-80dB min. |
| LO re-radiation |
<-60dBm |
| |
|
| Interface |
|
| Data rate |
DC - 32kbps (NRZ) |
| Levels |
5V CMOS |
|
|
| |
|
Programming the RDL2
As supplied, the RDL2 is set to default
channel zero. To change this preset, it is necessary to
enter setup/program mode.
The RDL2 is programmed through the
same TXD / RXD pins that is used for sending/receiving
data. An RS232 terminal emulator (such as Aterm or HyperTerminal)
is an ideal tool.
To connect to a true RS232 device,
inverting RS232-CMOS level shifters must be used. Maxim
MAX232 or equivalent are ideal, but simple NPN transistor
switches with pull-ups often suffice. With typical microcontrollers
and UARTs, direct connection is possible.
To enter program mode the SETUP pin
(pin 11) must be held low at turn-on, or during a change
of TXE pin state. In this mode the radio link is disabled,
but the TXD / RXD pins become a 9600 baud programming
interface. (Bytes received are echoed back on the RXD
pin).
In 'setup' the unit will only
respond to certain command strings:
| CHAN0
to CHAN4 <CR><LF> |
These commands select
one of 5 preset channels |
| |
|
|
A RDL2 will only communicate with a unit set to
the same channel.
Channel number is stored in volatile memory. On
power-up the RDL2 reverts to the default in EEPROM
(as supplied this is always Channel 0)
|
| |
|
| SETPROGRAM <CR> |
Writes the current
set address into EEPROM as the new default.
A tilda character (~, ascii 126dec) sent by the unit
indicates end of EEPROM write sequence |
| |
|
| (these commands are
normally only used for factory diagnostics) |
| NOTONE <CR> |
Transmit unmodulated
carrier |
| LFTONE <CR> |
Transmit carrier modulated
with 8KHz squarewave |
| HFTONE <CR> |
Transmit carrier modulated
with 16KHz squarewave |
| # <CR> |
Transmitter off |
| A Carriage Return
'<CR>' (00Dhex) should be entered after each
command sequence to execute it. |
| Releasing the SETUP
pin to high state returns the RDL2 to normal operation |
|
| |
|
| |
|
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 16cm (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
de-tuning.
|
| |
| |
A
|
B
|
C
|
| |
Whip
|
Helical
|
Loop
|
| Ultimate performance |
***
|
**
|
*
|
| Easy of design set-up |
***
|
**
|
*
|
| Size |
*
|
***
|
**
|
| Immunity proximity
effects |
*
|
**
|
***
|
|
| |
| 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. |
| |
|
Figure 4: Antenna types |
|
| |
| Ordering
information |
| Part
Number |
Description |
Frequency
band |
Maximum
data rate |
| RDL2-433-32 |
Transceiver |
433.925 - 434.565
MHz |
32kbps |
| RDL2T-433-32 |
Transmitter only |
433.925 - 434.565
MHz |
32kbps |
| RDL2R-433-32 |
Receiver only |
433.925 - 434.565
MHz |
32kbps |
|
| |
|
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:
Licensing
policy manual
|
 |
