ER400RS EASY RADIO, ER400RS Datasheet - Page 5

• Manufacturer Part Number: ER400RS
• Description: MODULE, RX, FM, 433MHZ
• Manufacturer: EASY RADIO

Specifications of ER400RS

• External Depth: 4mm
• External Length / Height: 14mm
• External Width: 37mm
• Frequency: 433MHz
• Operating Temperature Max: 65°C
• Operating Temperature Min: -20°C
• Rf Sensitivity: -105dBm
• Range: 250m

There is no ‘handshaking’ provided at either the transmitter or receiver. The user should therefore ensure
that sufficient time is allowed for the completion of transmission and reception of data. The Timing
Specifications detail these requirements (see page 8). Transmitter Host (A) must allow time for the ‘Over Air’
transmission and for the receiving Host (B) to unload (and process) the data before sending any more new
data. The receiver Host (B) must always be ‘ready and waiting’ for data to arrive. It should be possible to use
fast response ‘interrupts’ without any loss of data.
With such a ‘one-way’ (simplex) system there is no confirmation of the satisfactory reception of the data and
for added reliability it is recommended that the data be sent, perhaps, repetitively several times. For
increased reliability the use of transceivers (which can acknowledge packet reception) is recommended.
Easy-Radio services do not provide automatic acknowledgement (or re-tries) but these can be provided by
the users application.
LPRS Data Sheet
Easy -Radio ER400TS, ER400RS & ER400TRS 1-1.doc
A. Host (A) sends serial data to the Easy-Radio Transmitter (A). The data must be continuously
B. After detecting either the ‘End of Data’ gap or the ‘Buffer Full’ condition the controller enables RF
C. After checking the data for integrity the Data within the receive buffer of Easy-Radio Receiver (B) is
streamed at the selected baud rate and it fills an internal transmit buffer until either 128 bytes have
been received or a gap of two bytes is detected.
transmit and sends a fixed 10mS preamble followed by the data in the buffer which is Manchester
encoded at 19,200 Baud for efficient transmission across the RF link. Any Easy-Radio receivers
within range that ‘hear’ the transmission will simultaneously lock onto the preamble, decode the data
and place it into their receive buffers.
then sent continuously to the host at the selected baud rate.
A
B
C
Easy -Radio ER400TS Transmitter, ER400RS Receiver & ER400TRS Transceiver
Two Byte Delay for 'End of Data'
Figure 6 Serial Data
Copyright LPRS 2003. March2004
Host (A) sends serial data to Easy-Radio (A)
Easy-Radio (A) Transmits Over Air
Easy-Radio (B) Receives & Decodes
Easy-Radio (B) sends serial data to Host (B)
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