Omron NT-SERIES - SUPPORT TOOL FOR WINDOWS V4, Руководство по эксплуатации

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7-2 Section Numeral Memory Table
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entry is allocated. This setting is valid only for the NT21, NT31, NT31C, NT631,
and NT631C. With other PT models, numeric values are always treated as BCD.
BCD: The content of an allocated word is regarded as BCD
(binary coded decimal).
When the content of an allocated word is read, it is stored as signed
binary data. If F is set at the most significant digit position in the allo-
cated word, the content is regarded as a negative value. If an error is
found in the content of an allocated word (A to E at the most significant
digit position or A to F in other than at the most significant digit position),
the read out content is not stored in a numeral table. (The previously
stored content remains in the numeral table.)
When data is written to an allocated word, the signed binary data in the
numeral memory table entry is converted into BCD before writing. If a
negative value is written, F is entered at the most significant digit posi-
tion. (In this case, the number of storable digits is reduced by one.) If
the number of digits in the content of a numeral memory table entry is
greater than the number of digits of the allocated word in the PC (PLC),
only the numeric value is written from the least significant digit value.
Binary: The content of an allocated word is regarded as binary data.
When reading the content of the allocated word, the read content is
stored in a numeral memory table entry without change.
When writing a numeric value to the allocated word, the content of the
numeral memory table entry is written as it is. If the number of digits in
the content of a numeral memory table entry is greater than the number
of digits of the allocated word in the PC (PLC), only the numeric value is
written from the least significant digit value.
System: Conforms to the setting for [Numeral Display Type] of [System] in the
PC (PLC) Configuration.
Words
Specify the number of words to be allocated to a numeral memory table entry.
The possible specifications are 1 and 2.
If the setting is 1 word, the 4-digit BCD or binary data is shared by the PT and
PC (PLC).
If the setting is 2 words, the 8-digit BCD or binary data is shared by the PT and
PC (PLC).
When the setting is 2, the 1st to 4th digit data is allocated to the lower digit word in
the PC (PLC) and the 5th to 8th digit data is allocated to the higher digit word.
PT models other than the NT21, NT31, NT31C, NT631, and NT631C
If the setting has been made to display a sign, one digit (bit 4) in the most signifi-
cant digit position is regarded as representing a sign; if F (1111 in binary) is set,
the numeric value is regarded as negative and if any other code is set, the numer-
ic value is regarded as positive. Therefore, if the numeric value is displayed with
a sign, the maximum number of significant digits of a negative value is 3 if 1 word
is set and 7 if 2 words is set.
Example: When 1 word is set, the value –123 is treated as F123 in hexadecimal
in a numeral memory table entry.