Chapter 3 – Rockwell Automation 1771-SPI,D17716.5.122 SPI PROTOCOL INTERFACE User Manual
Page 31

Defining Command and Status Blocks
Chapter 3
3-9
Table 3.H
Word/Bit Definitions for the Custom Data Block (CDB)
Word
Number
Title
Range
Description
SPI Device ID starts at 00100000 20
Must use the SPIĆspecified device ID.
1
Determine
Configuration
DC
000= Standard
001 = Custom
010 = Random Data
011 = Random Data Open
Use 001 for custom configuration
stored in SPI RAM.
Not used
2
Device
Address
32 to 255 decimal data
Use the address that you selected on the
device with switches.
2
Zone
Address
48 to 255 decimal data
Use for temperature control devices, only.
Otherwise, zero.
3 and 4
Not used
Not used
stating at
5
BitĆcommand
word
0 to 255 decimal data
BitĆcommand words must match the
corresponding SPI codes that you loaded in
the CCB in type, quantity and order.
:
:
:
:
two words
per
Numeric
preset
(32Ćbit)
0 to 32,767 decimal data
Numeric setpoints, such as alarm limits, must
match the corresponding SPI codes that you
loaded in the CCB in type, quantity and order.
:
:
:
:
two words
per
ASCII
string
(32Ćbit)
0 to 32,767 decimal data
ASCII strings such as SPI Revision must
match the corresponding SPI codes that you
loaded in the CCB in type, quantity and order.