Nematron Pointe Controller - Manual (Page 318)

Appendix B: Flow Chart Command Reference Pointe Controller User Guide
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B.4 Diagnostics Commands
Diagnostics commands (in a Process block ) are used to read from and write to the
diagnostic items that are associated with each Input, Memory, and Output tag.
About Diagnostic Items
Every Input, Memory, and Output tag has associated with it three metadata
registers, plus a fourth register for Input and Output tags only. These registers are
allocated automatically when each tag is defined in Logic Memory, and they can
be manipulated independently of the tag’s primary value.
The four metadata registers – also called “diagnostic items” – are:
Diag Fault Bit – This item is used simply to indicate whether a fault
condition exists on the specified tag. The item occupies a single bit, which
can be toggled between 0 and 1.
Diag Fault Level – This item can be used to indicate escalating levels of
fault on the specified tag. The item occupies a 32-bit register.
Diag Status Code – This item can be used to record more complex error
codes on the specified tag. The item occupies a 32-bit register.
Error Status Bit – This item, available only on Input and Output tags, is a
special flag that is used to notify the program when an I/O error has been
encountered (see below). The item occupies a single bit, which can be
toggled between 0 and 1.
PointeControl itself does not utilize the Diag Fault Bit and Diag Fault Level items;
you are free to implement your own custom routines that write to and read from
these items, using the Diagnostics commands described below as well as the Diag
Fault Bit Test option of decision-type blocks (
If/Then , Repeat/Until , and While
Loop ).
However, PointeControl does internally utilize the Diag Status Code and Error
Status Bit items. For each
I/O point on the Pointe Controller unit (and on any
connected OptiLogic RTUs ), the controller automatically notes I/O errors
encountered during runtime and logs them on the Input or Output tag associated
with the affected point. When an error is encountered, the tag’s Error Status Bit is
set to 1 and the error code is copied to the tag’s Diag Status Code. Possible error
codes include:
CODE DESCRIPTION
0x00000200 (512) I/O module or operator panel not found
0x00000400 (1024) OptiLogic RTU not found
0x00004000 (16384) No value read yet
0x00040000 (262144) System error
0x00200000 (2097152) Communication error