Rockwell Automation 1770-KF2 Data Highway or Highway Plus Interface Module User Manual - Manual (Page 133)

Message Packet Formats
Chapter 5
5-54
The following example shows a type “A” (array) type/data parameter.
The array data type includes one descriptor as part of its data field. This
descriptor must be counted as part of the data field size:
Bit 76543210
10010111
00001001
01000010
ID in Next 1 Byte
Size = 7 Bytes (6 Data Bytes Plus 1 Descriptor Byte)
Integer, Size = 2 Bytes Each
Integer 1,
00000000
00000000
11111110
ID = 9 (Array)
Integer 0,
11111111
11111111 Integer 2,
(MS)
(LS) Value = –2
(LS) Value = 0
(MS)
(LS) Value = 255
(MS)
00000000
Not all sizes are legal for all formats. The “END” data type always has a
size value of zero (0), and the “B” data type will either have a size value
of 4 (single precision or 8 (double precision). Each of the Allen-Bradley
predefined structures has a fixed size.
Upload All Request
Use this command before uploading a complete system to place the
processor in an Upload mode (T50 terminal displays “Download” mode).
A no privilege error is returned if the programmed device does not have
the privilege of placing the processor into an Upload mode. This error
occurs when:
the processor is in Run or Remote Run mode (must be in Program or
Remote Program mode),
the processor is being edited, or
some other station is already downloading to the processor.