SMX2-XXX-5 Radiometrix, SMX2-XXX-5 Datasheet - Page 3

• Manufacturer Part Number: SMX2-XXX-5
• Description: Small Multi-channel UHF Transceiver
• Manufacturer: Radiometrix

Pin Description
Pin
1a
2a
3a
4a
5a
6a
7a
8a
1b
2b
3b
4b
The 'modem' mentioned is a 1200 baud RS232 semi-intelligent unit (Transmit keyed when valid serial
data is present, so no separate TX control needed. Coding in the datastream also permits the receiver to
ignore noise and only output valid serial data) This is a half duplex unit, so collisions between
transmitted and received packets must be dealt with by the user (if transmit data is sent to the unit
then a transmit burst commences immediately and the contents of the receive data buffer is lost)
Pin
1a
2a
3a
4a
5a
6a
7a
8a
1b
2b
3b
4b
NOTES:
1. No inversion occurs between TXD and RXD. However AF out is inverted relative to TXD.
2. Parallel channel selects are active LOW and have internal pullups to 4V
3. There are no pullups on the open collector outputs.
4. The software incorporates a 1200 baud modem, compatible with that implemented in other
Radiometrix Ltd
Radiometrix narrowband units ( i1200 tones and format ). Modem operation is selected by the
SETMOD command. TXE pin (6a) becomes an RS232 input, and RS232 compatible data is output
on the RXD pin (5a). If true +/- levels are desired then an inverter and a MAX232 should be used on
data out.
Name
RSSI
Vcc
TXD
AF out
RXD
TXE
PGM
0V
0V
S0
S1
S2
Name
RSSI
Vcc
NC
NC
MOD RXD
MOD TXD
PGM
0V
0V
S0
S1
S2
Pin description of SMX2 with Modem mode selected
DC supply input. (4.2 – 15V at 50mA max.)
DC supply input. (4.2 – 15V at 50mA max.)
Function
DC level between 0.5V and 2.5V. 60dB dynamic range
DC coupled input for TTL/ CMOS logic.
500mV p-p audio. DC coupled, approx 0.8V bias.
Open collector output of data slicer. Need external pull-up
Transmit enable. Low = RX mode. High = TX. (10k
Serial programming / control input (true RS232)
Ground
Ground
Parallel channel select LSB
Parallel channel select
Parallel channel select MSB
Function
DC level between 0.5V and 2.5V. 60dB dynamic range
Leave unconnected
Leave unconnected
Open collector RS232 compatible data output
RS232 data input
Serial programming/control input (true RS232)
Ground
Ground
Parallel channel select LSB
Parallel channel select
Parallel channel select MSB
Figure 3: SMX2 footprint (Top) view
SMX2 Data Sheet
pull down)
page 3