Allen-Bradley 1734-SSI - Communicate Real-time Information

22 Rockwell Automation Publication 1734-UM007E-EN-P - October 2015
Chapter 3 Communicate with Your Module
Communicate Real-time
Information
The Synchronous Serial Interface Absolute Encoder module uses data bytes
composed into assemblies to communicate real-time input and output data over
an I/O connection, as well as non-real-time module information by using an
Explicit Messaging connection.
• Assembly 101 is produced data sent by the module over an I/O or Explicit
Messaging connection.
• Assembly 102 is consumed data that is received by the module over an I/O
or Explicit Messaging connection.
• Assembly 103 is configuration data that can be read or changed over an
Explicit Messaging connection.
Byte Bit Description
Produce 8 76543210Status Byte 0
C2ST C1ST C2R C1R INC DEC RUN I1
Produce 9 76543210Status Byte 1
(1)
RES RES RES LHON IDF
(1)
CCE CCF SPF
Consume 0 76543210Master ACK
Byte
(2)
RES RES RES SCMP2 SCMP1 CC2 CC1 LACK
Consume 1 76543210CONS1
RES RES RES RES RES RES RES RES
1 Monitor IDF to determine the validity of the produced data. If IDF=1, the SSI data is false.
2 The master must provide the Master ACK Byte in order to receive the polled Produced bytes 0…9.
I1 = Input 1 Status (1 = Input 1 ON, 0 = OFF)
RUN = SSI Clock Output Status (1 = Clock Output ON, 0 = OFF)
DEC = SSI Data Count Decreasing (1 = Decreasing, 0 = Not Decreasing)
INC = SSI Data Count Increasing (1 = Increasing, 0 = Not Increasing)
C1R = Comparator 1 Value Reached (1 = Value Reached, 0 = Not Reached)
C2R = Comparator 2 Value Reached (1 = Value Reached, 0 = Not Reached)
C1ST = Comparator 1 Active (1 = Active, 0 = Not Active)
C2ST = Comparator 2 Active (1 = Active, 0 = Not Active)
SPF = SSI Sensor Power Fault (1 = Fault Present, 0 = No Fault)
CCF = Coprocessor Configuration Fault (1 = Fault Present, 0 = No Fault)
CCE = Coprocessor Communication Error (1 = Error Present, 0 = No Error)
IDF = SSI Input Data Fault (1 = Fault Present, 0 = No Fault)
LACK = Input 1 Latch Acknowledge (1 = Unlatch, 0 = No Fault)
CC1 = Clear Comparator 1 (1 = Clear)
CC2 = Clear Comparator 2 (1 = Clear)
SCMP1 = Set Comparator 1 (1 = Comparator 1 is Active)
SCMP2 = Set Comparator 2 (1 = Comparator 2 is Active)
RES = Reserved (Bit = 0)
LHON = Latched Data is Stored (1 = Latched Data Present, 0 = Latched Data Not Present)