Omron NT21 Reference Manual page 211

Inputting Numeric Values
Reference: Numeral memory table entries store numeric values as signed binary data.
Note that if the number of digits of the numeric value is greater than the total of
the settings for Integer and Decimal, an error occurs and is displayed for all the
digits.
Example: Displaying 123456
Setting for Integer = 8; setting for Decimal = 0:
Resulting display: 00123456
Setting for Integer = 4; setting for Decimal = 4:
Resulting display: 0012.3456
Setting for Integer = 2, setting for Decimal = 4:
Resulting display: 12.3456
Setting for Integer = 1, setting for Decimal = 4:
Resulting display:
For hexadecimal display, only the number of digits of the integral part is speci-
fied.
Input Numeric Value and Stored Data
The range of numeric values that can be input and the conversion method for
storage depend on the following settings.
Display Type (Decimal/Hexadecimal)
Display Sign (whether or not negative values are displayed)
Conversion Depending on Display Type
The data is converted for storage in a numeral memory table entry as follows
depending on the setting for Display Type:
Decimal:
The numeric value input in decimal is converted to signed binary data and
stored in the numeral memory table entry.
Hexadecimal:
The numeric value input in hexadecimal is stored in the numeral memory
table entry without alteration.
When the word allocated in the host is input to a 1-word memory table
entry, the input value is treated as 4-digit (16-bit) signed binary data so it is
converted to 8-digit signed binary data before being stored.
For example, if a value of 8001 hexadecimal is input to a 1-word numeral
memory table entry, it is recognized as a negative value because the most
significant bit is ON. The value actually stored in the numeral memory
table entry is FFFF 8001 hexadecimal.
Permissible Input Range
When inputting values into numeral memory table entries, the permissible input
range is affected not just by the Display Type and Display Sign but also the Stor-
age Type and Words settings. (When words are not allocated for the numeral
memory table entry in the host, the Words setting is treated as 2 words.)
Section 2-12
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