OmniTek OTR 1001, Руководство пользователя

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OmniTek OTR 1001 User Guide, v3.1 I-6
Each Packet is composed of a number of bit fields, the descriptions of which are given by
individual BitField elements. At present each PacketType element must include at least one
BitField element. It may also include Break statements and Switch elements.
BitField Statements
Each BitField element describes a group of bits that together make up a single item of
information within the packet. They typically comprise a BitField statement together with a
sequence of Bit statements but, where appropriate, they may also include Determinant
statements.
There must be at least 1 BitField element within any PacketType element but there is no
maximum number.
Note: A bit field may stretch across multiple words, but at present may not
go above 32 bits in length.
<BitField
Attributes
>
…
</BitField>
Attributes:
FieldName=" string " (required)
where string is a suitably descriptive name for the Bit Field. This name will be used to label the
associated data in the DataView, subject to the setting of the
Label
attribute. The name used
does not have to be unique.
e.g.
FieldName="CH 1 Audio Data"
BFWordOffset=" integer " (required)
where integer identifies the word within the packet at which the bit field starts, by identifying its
offset from the start of the UDW block/the start of the current repetition if the PacketType
Repetative
attribute has been set to
"true"
.
e.g. BFWordOffset="2"
FieldLength=" integer " (required)
where integer is the number of bits in the reconstructed bit field. At present, this is limited to a
maximum of 32 bits.
e.g.
FieldLength="22"
Repeated=" boolean " (required)
This distinguishes between bit fields that are repeated and those which are not. boolean is true
where the bit field being described is repeated within a repetitive PacketType, but otherwise
should be
false .
e.g. Repeated="true"
Repitions=" integer "
Where Repeated is true , integer gives the number of repetitions.
e.g. Repitions="3"
BFType=" BitFieldType "
This is used where the BitField statement is part of a Switch or Case element to specify how the
value of the bit field should be treated.
BitFieldType may be either Selective , Conditional or
Default ..
e.g. BFType="Selective"