Rockwell Automation 1747-SDN SLC 500 DeviceNet Scanner Module User Manual - Manual (Page 19)

Publication 1747-UM655B-EN-P - June 2007
Before You Begin 19
1747-SDN Module Data
Tables To manage the flow of data between your SLC 500 processor and the
network devices, the 1747-SDN module uses the following data tables:
•
Scanner configuration table (SCT)
•
Scanlist table (SLT)
•
Device input data table
•
Device output data table
•
Device active table
•
Device failure table
•
Client/Server transaction tables
You can configure the first two of these data tables through
RSNetWorx for DeviceNet software.
•
Scanner configuration table (SCT)
•
Scanlist table (SLT)
These two tables are stored in the 1747-SDN module’s nonvolatile
memory and used to construct all other data tables.
Scanner Configuration Table (SCT)
The SCT controls basic information your 1747-SDN module needs to
function on your DeviceNet network. It tells your 1747-SDN module:
•
if it can transmit and receive input and output data.
•
how long it waits after each scan before it scans the devices
again.
•
when to send out its poll messages.
Scanlist Table (SLT)
The SLT supports I/O updating for each of your devices on the
network. It also makes it possible for your 1747-SDN module to make
device data available to your SLC processor. The SLT tells your
1747-SDN module:
•
which device node addresses to scan.
•
how to scan each device (strobe, poll, change of state, cyclic, or
any valid combination).
•
how often to scan your devices.
•
exactly where in each device’s total data to find the desired data.