DS601-4

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©2004 Reg. No. 227 4001, ENGLAND

Page 6

Smart Com Radio Transceiver IC

RF600T

the buffer will be transmitted to the host. When the RTS line is taken high then data flow will be inhibited

and until the buffer is empty the device will not be able to perform any other operations.

Packet Size and Timing

The following information is provided to aid in timing calculations for the RF data transmission.

Element

Size (bits)

Modes Present

Run-In / Pre-amble

76

Both

Sync Pattern

4

Both

Start Bit

1

Both

Command Byte

8

Both

Source Address

32

Addressed only

Destination Address

32

Addressed only

Data Bytes

xxx

Both

Checksum

8

Both

Addressed mode packet overhead:

Addressed Transmission time, presuming 200uS element time, no idle period:

Please note this timing is for RF transmission only the RS232 communications timing is not included.

Radio Module Interface

The interface to the radio module(s) consists of the following signal and control lines:

TxR

Serial data output from the RF600T to the radio module.

RxR

Serial Data input to the RF600T from the radio module.

TXEN

When active low the RF Transmitter is enabled

RXEN

When active low the RF Receiver is enabled

Radio Module Communications

All data communications between the radio modules are carried out using an R. F. Solutions proprietary

data protocol with Manchester coding. This protocol includes a pre-amble and synchronisation header

followed by address and control bytes, data and a CRC check. Element timing is selectable at either 400

us or 200 us using the HBAUD option as described above.

Radio Module Control

The RXEN and TXEN control lines are used to enable or disable the receiver and transmitter modules – or

in the case of a transceiver module, to control the direction of operation. The logic of these outputs is such

that when the RF600T wishes to transmit, it will take the RXEN line high and the TXEN line low. When the

RF600T wishes to receive, it will take the RXEN line low and the TXEN line high.