Installation manual

Publication 1747-RM001G-EN-P - November 2008
12-46 SLC Communication Instructions
CEM Instruction Setup Screen Parameters
The following sections provide parameters for the CEM instruction setup
screens.
Parameters for This Controller on the General Tab
• 1747-SCNR Slot
This drop-down field lists all of the local slots that contain ControlNet
scanner (1747-SCNR) modules within the IO Configuration. Select the
slot number of the particular scanner module that this explicit message
will be initiated through.
• Size in Words (Receive Data)
This field defines the size of the integer data file that will be used to
store the data that is returned by this explicit message command. For
best performance, define this file size to only be as large as is required. If
no receive data is expected, you may leave this field at 0 and no receive
data file will be defined. If unsure of how much data will be returned,
you may select up to the maximum size of 250 words, and then reduce
the size later based on experience.
• Size in Words (Send Data)
This field defines the size of the integer data file that will be used to
store the data that is sent along with this explicit message command. For
best performance, define this file size to only be as large as is required. If
no send data is required, you may leave this field at 0 and no send data
file will be defined. If unsure of how much data will be sent, you may
select up to the maximum size of 248 words when defining the
instruction, and then reduce the size later based on experience.
• Data Table Address (Send Data)
If Size in Words (Send Data) is non-zero, then this field requires a
starting integer (N) file address for storing the Send Data.
• Data Table Address (Receive Data)
If Size in Words (Receive Data) is non-zero, then this field requires a
starting integer (N) file address for storing the Receive Data.