Rockwell Automation 1771-SPI,D17716.5.122 SPI PROTOCOL INTERFACE - Manual (Page 35)

Defining Command and Status Blocks
Chapter 3
3-13
CDS Resulting from CDB
The SPI module responds to CDB commands by reflecting the CDB back
to the PLC processor as the CDS (Table 3.L):
Table 3.L
Custom Data Status (CDS)
Word 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
1 0 CR CE 0 DC Device Identification
2 Zone Address Station Address
3 Diagnostic Word: If the SPI module detects a fault, it sets an error code to help identify the cause of the fault
4 0 0 0 0
starting at 5,
up to 64
If no communication fault, reflects all the commandĆcode pairs that you entered in CCB. Reports zero for a fault.
Table 3.M
Bit/Word Definitions for Custom Data Status (CDS)
Word
Number
Bit
Number
Title Range
0Ć7 Block ID 00100000 to 11111111
1
8Ć10
Determine
Configuration
DC
000= Standard Configuration
001 = Custom Configuration
010 = Random Data Configuration
011 = Random Data Open Config
100 = Store Configuration
101 = Read Configuration
110 = Overwrite Configuration
111 = Clear Configuration
11 Reserved zero
12
Command Executed
CE
Bit 12 = 0 - Command not executed
Bit 12 = 1 - Command executed
13
Command
Response CR
Bit 13 = 0 - response to a queued read
Bit 13 = 1 - response to a CDB
14Ć15 Reserved zero
0Ć7 Station Address 32 to 255 decimal data
2
8Ć15
Zone Address
(temperature control)
48 to 255 decimal data
3 0Ć15 Diagnostic Word error code if SPI module detected a fault
4 Not used zero
5
up to 64
0Ć15 or
0Ć32
Reflected command,
specified status, or
zero
For a CDB, reflects the commandĆcode pair.
For a polling sequence, returns specified status.
For a fault, clears the word.