tr2m-458-5 Radiometrix Ltd, tr2m-458-5 Datasheet - Page 4

• Manufacturer Part Number: tr2m-458-5
• Description: Multinarrow Band Fm Multi-channel Uhf Transceiver
• Manufacturer: Radiometrix Ltd

TR2M can be directly interfaced to a host microcontroller which can generally be powered by the
regulated +4.4V output on pin 8 of TR2M. 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 P1-P3 pins low. Channel select pins of TR2M have internal pull-up to 4V supply rail,
hence channel selection operate on inverted logic.
Digital Received Data Output (RXD) pin is an open collector output, which should be pulled-up to
required voltage swing level (e.g. +4.4V or Vcc).
TR2M 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.
TR2M 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 C10) of the TR2M and SGN (pin 5) of
DB9M connector should be either connected to common ground or pin C9 of the TR2M.
The whole frequency/channel table is user reconfigurable to 128 channels within 5MHz band of supplied
frequency subject to regulatory band limits. Serial Channel Selection via PGM pin gives access to the
whole of regulatory band allocation for 433.05MHz-434.790MHz (69 channels) or 458.525MHz-
458.925MHz (23 channels).
Radiometrix Ltd
Figure 4: TR2M interfaced to host microcontroller and serial port for configuration
TXE (MOD TX_ON) (C1)
Channel
0
1
2
3
4
5
6
7
AF in (MOD NC) (C3)
P2 (MOD RXD) (C12)
RXD (MOD NC) (C7)
P1 (MOD TXD) (C11)
SQF (MOD NC) (C5)
TXD (MOD NC) (C2)
P3 (MOD NC) (13)
+4.4V out (C8)
AF out (C6)
PGM (C10)
GND (C9)
RSSI (C4)
P3:P2:P1
111
110
101
100
011
010
001
000
Carrier Detect
10kΩ
TR2M Data Sheet
100nF
433MHz band
433.050
433.075
433.100
433.125
433.150
433.175
433.200
433.225
Data In
Transmit Enable
Data Out
VDD
Parallel
Channel
Select
ADC
458MHz band
458.525
458.550
458.575
458.600
458.625
458.650
458.675
458.700
6
7
8
9
4
5
1
2
3
TXD
SGD
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