Power up sequence – Rockwell Automation 1336T Function Block Prog. Manual, Series A/B User Manual

Page 53

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3–5

System Interactions

1336 FORCE — 5.9 August 1995

If you do a Recall on the linear parameter area before doing a Recall
on the function block area, no function blocks will exist in RAM.
When the linear parameter Recall is executed, it cannot build link B
because the function block that provides the data to the linear
parameters does not yet exist in RAM. This will cause a drive soft
fault to occur.

The system does not automatically clear a link that was valid but has
become invalid. You need to clear the link or adjust the link to point
to a valid parameter or node before you can clear the fault.

The function block fault read service returns the reference of the first
node with an invalid link reference. You may clear links individually,
or you can clear all links at once.

When using DriveTools, you can access the function block BRAM
functions from DriveBlockEditor EEPROM selection and the linear
parameter BRAM functions from DriveManager. For additional
information about the linear parameter value, link, and BRAM
services, refer to the PLC Communications manual.

Whenever you power up the system, the drive does the following:

1. Performs a linear parameter BRAM Recall function to restore the

linear links and parameter values from BRAM to RAM

2. Builds the linear parameter link scanner. While building this list,

links which reference function block nodes are skipped. No
function blocks exist yet.

3. Performs a function block Init.

4. Performs a function block Recall to restore the execution list

values, all node values, and link references to the appropriate
RAM data tables from their associated counterparts within
BRAM.

5. Activates the function block compiler.

6. Processes all function block links when the compilation is

complete.

7. Goes over the linear parameters and adjust links from linear

parameters to function block nodes. This step processes any linear
destination parameters that were not linked in step 2 because they
referenced function blocks.

8. Activates the 20 millisecond function block application and

allows drive enable if no function block soft faults occur during
processing.

Power Up Sequence

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