Rockwell Automation 1203-SM1 SLC to SCANport Communication Module - Manual (Page 30)

4–2 Using Enhanced Mode
Publication 1203–5.9 –– October 1996
What Are Datalinks?
Datalinks let you cyclically transfer parameter values to and from a
SCANport device (provided that the SCANport device supports
datalinks). By using datalinks, you can change the value of a
parameter without using the SLC to SCANport messaging function.
Each datalink consists of two 16–bit words of input and two 16–bit
words of output when enabled. Up to 8 words in and 8 words out of
data are available if supported in the connected SCANport device.
SCANport devices that support this function have a group of
parameters for datalink configuration. These parameters are
identified as Data In A1–D2 and Data Out A1–D2. To use datalinks,
you need to:
1. Set up a configuration file, called a G file, to enable the datalinks
from the SLC to SCANport module side.
2. Configure or link the Data In A1–D2 and Data Out A1–D2
parameters in the SCANport device.
Setting up the G file is covered in more detail later in this chapter.
What Is Safe State Configuration Data?
You can select constant values that your SLC to SCANport module
will maintain in the event of an SLC processor mode change or error.
These constant values are referred to as safe state data. When the
SLC is placed in program mode or an SLC fault occurs, the control
outputs can be set to automatically switch to the constant values set
in the safe state data words. This lets you define a safe operating
state for controlled devices that depend on a pre–programmed output
from the module.
!
ATTENTION: Use the G file to configure your safe
state values based on your knowledge of how the
SCANport devices connected on each channel operate.
Refer to the manual for your SCANport device for
additional information.
Refer to Chapter 2 for the DIP switch configuration for
fault/program state.