Rockwell Automation 1771-QB Linear Pos. - Manual (Page 71)

Interpreting ModuleĆtoĆPLC Data
(READS)
Chapter 6
6Ć10
Diagnostic Information (words 4, 5 and 8, 9)
After a reset command or powerup, the module displays diagnostic information
so you can detect parameter block errors. (The module doesn’t accept command
blocks until after it receives a valid parameter block.)
Use the diagnostic words to determine the cause of a block transfer error. The
block ID identifies the last block received by the module. It is updated with
each block transfer. The word pointer identifies the location of the problem and
the error code determines the nature of the problem.
The diagnostic information is displayed in BCD format. See Appendix H for an
explanation of numbering formats.
Figure 6.5
Diagnostic Format
50054
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
0 0 0 0 0 0
Block ID:
0 = Not applicable
1 = Parameter
2 = Setpoint
3 = Command
4 = Motion
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Word pointer Ċ This BCD
number indicates which word
within the block is in error.
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Error Code Ċ This BCD number
indicates the error that occurred.
The second of the two diagnostic words gives the error code and points to the
word where the error occurred. Table 6.A shows the error codes.