Schweitzer Engineering SEL-2032, Instruction Manual

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7.15
Date Code 20120126 Instruction Manual SEL-2032 Communications Processor
Settings
Automatic Message (SET A) Settings
Character String (Parse = 3)
This technique retains all numbers and characters in a character string. For
example, if you selected the Character String option and set the number of
responses (NUM
x ) to 60, the example message is parsed as follows:
Message: “This is a 2030 message with numbers 10, -6.2, and 2,459.884”
Parsed response: “This is a 2030 message with numbers 10, -6.2, and
2,459.884”
For this parsing method, the SEL-2032 always appends a NULL character
(00h) to the end of the parsed response before storing it to the database. This
means that the NUM
x setting must be set to a value one greater than the
expected number of response items. The above string is actually 59 characters
in length, yet the NUM
x setting was set to 60.
If you set the number of responses less than 60, the parsed result is truncated;
if you set the number of responses greater than 60, the result includes extra
trailing nulls. These are nonprinting characters, so you will not see any
difference when using default data viewing methods, i.e., “...d 2,459.884.”
Integer String (Parse = 4)
This technique stores each pair of received bytes in a register, most-
significant-byte first. The Integer String option is primarily useful for
capturing data from devices that send data in binary words. Because this
parsing option uses both upper and lower bytes of each register, it stores data
in fewer registers (less space) than the Character String option. You can
retrieve data from these registers using the special strings designed to work
with a data word. See
Section 9: Protocols for more detailed information.
Integer String With XON/XOFF Encoding (Parse = 5)
This technique works just like Integer String, except each pair of received
bytes is compared to a set of special codes that are used to encode the XON
(11h) and XOFF (13h) characters. If one of the special codes is encountered,
the appropriate 11h or 13h character is stored. The encodings used are as
follows: a 99h followed by a 01h represents XON (11h), a 99h followed by a
02h represents a XOFF (13h), a 99h followed by a 03h represents a 99h. Since
99h is always encoded, any 99h that is received and is not followed by 01h,
02h, or 03h is ignored. For example, if you set the parse option to Integer
String with XON/XOFF encoding and set the number of items (NUM
n ) to 4,
the following message is parsed as shown below (all data shown as
hexadecimal character codes):
Message: 019902109903249915FF9934C80B
Parsed result: 011310992415FF34
Notice that the NUM n setting applies to the number of “parsed” items, not to
the number of received items. This parsing method is useful when binary data
are being received while XON/XOFF flow control is enabled.
Flexible Parsing (Parse = 6)
This technique parses received characters according to a user-defined Decode
Equation. The Decode Equation identifies data types and search strings
expected in the received characters. Text strings that match the Decode
Equation are stored into the Data region.
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