OPC90 Server
7.3.1 Reading A Bailey Block
To retrieve existing block specification information, the block address must first
be written to the ADDR_RING, ADDR_NODE, ADDR_MODULE and
ADDR_BLOCK tags of this block. Once the address is written, the READ tag
can be set TRUE which instructs OPC90 to retrieve the block specifications. The
specification values are copied to the S01_VALUE through S63_VALUE tags.
The S01 through S63 tags are also updated with a description of each returned
specification. The FC tag will return the block function code number and the
FCNAME tag will return the name of the function code. Completion of the read
request is signaled when the READ tag is reset to FALSE. The MESSAGE tag
will also return a text message indicating completion of the read operation or the
reason for failure if the read cannot be completed. When the ACKNAK tag is
zero the request was successful, non-zero indicates an error occurred.
Since Bailey function blocks can have up to 63 specifications, tags exist for the
maximum number of specifications. The actual number of valid specifications for
any given block read can be determined by examining SX_COUNT tag or the
descriptions assigned to each specification (S01 through S63 tags). Null
descriptors indicate the specification number is not valid for the block read.
7.3.2 Tuning A Bailey Block
Some Bailey specifications can be modified while the block is executing. These
tunable specific
uch by the specification
aving the ‘T’
be used
TRU
at was changed by the OPC client will be included in the Bailey block tune
letion of the tune operation is flagged when the TUNE tag is
are called
ations and are indicated as s
description h
character in front of it. The tags S01_VALUE through
S63_VALUE can
to change the value of tunable specifications. When
the TUNE tag is set
E, any tunable S01_VALUE through S63_VALUE tag
th
operation. Comp
reset to FALSE. The MESSAGE tag will also return a text message indicating
completion of the tune operation or the reason for failure if the tune cannot be
completed. When the ACKNAK tag is zero the request was successful, non-zero
indicates an error occurred.
7.3.3 Reading The Entire Bailey Configuration
The entire Bailey configuration can be read using the READ and NEXT tags (also
see save command processing). First start by using the ADDR_RING,
ADDR_NODE, ADDR_MODULE, ADDR_BLOCK and READ tags to read block
zero which is the start of any given module configuration. Each time the NEXT
tag is set TRUE, the next block from the last one just read will be retrieved. The
returned specification values are copied to the S01_VALUE through S63_VALUE
tags. The S01 through S63 tags are also updated with a description of each
returned specification. The FC tag will return the block function code number and
the FCNAME tag will return the name of the function code. Completion of the
next read operation is flagged when the NEXT tag is reset to FALSE. The
MESSAGE tag will also return a text message indicating completion of the next
read operation or the reason for failure if the next read cannot be completed.
When the ACKNAK tag is zero the request was successful, non-zero indicates an
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