Nikon NWL860 Series, Руководство пользователя

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Chapter 3 Interface Specification
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4-7-5. Length Byte Count
Defines the number of bytes making up the length byte.
0 = Illegal, data format error
1 = 1-byte binary length byte (max. 255)
2 = 2-byte binary length byte (max. 64 K)
3 = 3-byte binary length byte (max. 7.99 M)
For list format, length represents the number of elements (lists or items) in the list.
The length byte of 0 has a special meaning, which is defined by the individual specification.
4-7-6. Length Byte
Defines the byte count required for the following data.
When the length byte is made up of more than one byte, the bytes are sent out in order, from
the upper byte.
The length byte consists of 1 to 3 bytes.
4-7-7. List
Defines the number of component data (elements) when the data consists of data in different
formats.
The format of the list header is the same as that of the item header.
Individual component data are defined by the item header.
4-7-8. Examples of Item and List
(a) Item containing one binary code 10101010
bit 87654321
00100001 Item with length byte 1
00000001 Byte length 1
10101010 Data byte
(b) Item containing three ASCII characters A, B, and C
01000001 Item ASCII, length byte 1
00000011 Byte length 3
01000001 ASCII character A
01000010 ASCII character B
01000011 ASCII character C
(c) Item containing (b) above and three binary numbers in 2-byte format
00000001 List, length byte 1
00000100 Number of elements 4
01000001 Item ASCII, length byte 1
00000011 Byte length 3
01000001 ASCII character A
01000010 ASCII character B
01000011 ASCII character C
01101001 Item 2-byte integer, length byte 1
00000010 Byte length 2
xxxxxxxx Upper byte for a number X
xxxxxxxx Lower byte for a number X