Invengo XC-RF300, Руководство пользователя

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Field Description
<SOF> Start Of Frame (01h)
<Address> This field is ignored by XC-RF300.
<Command ID>
In a command frame, the ID of the command that should
be executed. Command IDs are in the range 0000h-7FFFh
<Error Code>
In a response frame, the error code if an error occurred
during execution. Error codes are in the range
8000h-FFFFh. If no error occurred, the command ID is
repeated.
<Nb Data> The Data field length in number of bytes.
<Data>
In a command frame, the parameters for the command.
In a response frame, the return values associated to the
command.
<Checksum>
A checksum. This is the arithmetic sum off all previous
bytes.
The reader is never allowed to send data over its interfaces without having
received a command from the host.
A simple password-based security mechanism can be activated to prevent
unauthorized access to the reader. In such a case, the host system must first
execute a specific command to identify itself before being allowed to send any
other command.
For more information about StxNG protocol and a complete command set
description, please refer to XC-RF300 Designer’s guide.