Boolean is transferred on 1 byte (value 0 and 1). It means that for example Integer is transferred on 2 bytes (at first LOW and then HIGH byte). The format of the "data" field equals to the format of the data types on the computer. If the DST field has the value 254, then it goes about the "broadcast" message, it means that is sent to all computers in the network. If the DST and SRC fields have the value of 0, then it goes about the non-network protocol that differs from the network one the rather that the DST and SRC bytes are not included into the protocol at all. DST and SRC fields can hold values from 1 to 253. In general it goes about the network protocol, it means that there is the computer number in the message that receives the message ( DST=destination) and the computer that sends the message ( SRC=source), in the message. By this encoding using the DLE character we can achieve that STX, ETX, ACK, DLE and NAK occur only on those positions of the message where its real function is. Instead of that we send 2 bytes: DLE and then 82H. We want to transfer 1 byte of the value 02H in the data. It means that the protocol has a variable length of the message depending on message values!
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