3 ] basic format of transmission messages, Basic format of transmission messages – Denso BHT-6000 User Manual

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[ 3 ] Basic Format of Transmission Messages

Basically, the BHT-6000 transmits data as units of a file. First, it transmits a heading
text which includes the attribute information of a file (e.g., file name and the number of
data texts) to be transmitted. Following the heading text, it transmits the data text in
the file. A heading text and data text comprise a text.

In actual text transmission, the text is divided into several blocks, then a header,
terminator, serial number, receiver station’s ID, and CRC-16 (Cyclic Redundancy Check)
are added to each block. This procedure forms a transmission block. A set of
transmission blocks makes up one transmission message.

Shown below is an example of a transmission message formed with the BHT-Ir
protocol.

In the above figure, DLE SOH, DLE STX and DLE ETX are text control characters as
described in [ 2 ] Control Characters. An ID denotes the ID number of the receiver
station, expressed by two bytes. A serial number is expressed by a five-digit decimal
number, starting from 00001 to 32767, and identifies data texts. For the CRC-16, refer
to [ 6 ] CRC.

You can use the control characters for expressing IDs serial numbers, or text data.
For DLEs, type DLE DLE per DLE.

Data text 1

Data text 2

Data text n

Heading
text

Transmission
Message

Data text 1

Transmission
block

Transmission
block

Text

Heading text

TIP

Serial
number

Data text 2

Serial
number

Transmission
block

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