Nikon NWL860 Series, Manual

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Chapter 3 Interface Specification
3
4-6-8. Standard Message ID
For standard stream and function codes, see “4. Detailed Message Format” in Chapter 4.
4-6-9. Block No.
When the length of message data to be transmitted exceeds 244 bytes, the message is divided
into several blocks, and the blocks are sent separately. Block No. represents the order in which
they are transmitted.
* See “4-6-11. Multi-Block” in this chapter.
When the message consists of only one block, it is assigned Block No. 1.
4-6-10. E-Bit
Defines whether additional message blocks follow.
E = 0: More blocks follow.
E = 1: No blocks follow.
4-6-11. Multi-Block
When message data consists of more than one block, the data is referred to as a multi-block
message. One multi-block message can contain up to 32767 blocks (a total length of 7.99
Mbytes).
The first block of a multi-block message is numbered 1. All subsequent blocks are numbered in
order, with each assigned number incremented by one from the preceding.
Defined by the user
Stream
Reserved
by the
SECS
Function Code
0 1 – 63 64 – 127
0
1
63
64
255
Message to Transmit
Transmitted Message
Header
No. = 1 Header
No. = 2 Header
No. = 3
① ② ③
① ② ③
System Byte 1
System Byte 2
System Byte 3
System Byte 4
Source ID (Upper)
Source ID (Lower)
Transaction ID (Upper)
Transaction ID (Lower)
4-6-12. System Byte
System byte is classified as follows.