Radiometrix Ltd, RPC2A

page 6

asynchronous protocol. The nibbles are always sent in pairs to form a byte, the Least Significant Nibble

(bits 0 to 3) is transferred first, followed by the Most Significant Nibble (bits 4 to 7). Two pairs of

TX Request & TX Accept:

control the flow from the HOST to the RPC2A (download)

RX Request & RX Accept:

control the flow from the RPC2A to the HOST (upload)

A packet transferred between host and RPC2A consists of between 1 and 28 bytes, the first byte of the

packet is always the control byte.

↔ RPC2A transfers:

1. Data Packets:

To the transmitter or from the receiver

2. Memory Access:

To or from the RPC2A's memory

Byte Count (1-27)

00

0

Packet To Transmit

RPC2A

Byte Count (1-27)

00

0

Received Packet

RPC2A

0

6

5

7

5 bits

control byte

1 data byte

st

2

data byte

nd

3

data byte

rd

figure 6: RPC2A

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