2.2.2 SENDING AND RECEIVING DATA PACKETS
Data packets are sent to / received from remote FRPC2’s. They begin with a control byte with bit 7
cleared and may be of variable length and contain up to 60 bytes of user determined data.
figure 9: Control byte for data packet
The remainder of the bytes in the data packet are of the users determination.
The packet would usually be made up of a number of fields consisting of some
but not necessarily all of the following :-
Source address / ID
Destination address / ID
System ID
Packet count
Encryption / Scrambler control
Additional error check codes ( The FRPC2 performs it's own error checks)
Routing information ( for repeaters)
Link control codes (connect/disconnect/ACK/NAK etc.)
Data field
2.2.3 FRPC2 MEMORY ACCESS
The FRPC2’s EEPROM memory can be accessed by setting bit 7 in the control byte. Bit 6 (R/W flag)
defines a memory read or write. The bits left define the address.
figure 10: RPC2 memory access
Radiometrix Ltd, FRPC2
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RADIOMETRIX [ RADIOMETRIX LTD ]
