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2 Instructions
CP1E CPU Unit Instructions Reference Manual(W483)
Floating-point Math
Instructions
2
FVAL
FVAL
Applicable Program Areas
Operands
Operand Specifications
Flags
Function

FVAL(449) converts the specified ASCII text number (starting at word S) to a 32-bit floating-point num-

ber (IEEE754-format) and outputs the result to the destination words starting at D.

FVAL(449) can convert ASCII text in decimal or scientific notation if it meets the following conditions:

Up to 6 characters are valid, excluding the sign, decimal point, and exponent. Any characters beyond

the 6th character will be ignored.

Decimal Notation

Real numbers expressed with an integer and fractional part.

Example: 124.56

Instruction Mnemonic Variations Function
code Function
ASCII TO FLOATING-POINT FVAL @FVAL 449
Converts a number expressed in ASCII text (deci-
mal or scientific notation) to a 32-bit floating-point
value (IEEE754-format) and outputs the floating-
point value to the specified words.
Symbol
FVAL
Area Step program areas Subroutines Interrupt tasks
Usage OK OK OK
Operand Description Data type Size
S First source word UINT Variable
D First destination word REAL 2
Area Word addresses Indirect DM addresses Constants CF
Pulse
bits
TR
bits
CIO WR HR AR T C DM @DM *DM
S, D OKOKOKOKOKOKOK OK OK --- --- --- ---
Name Label Operation
Error Flag P_ER ON if the digits (integer and fractional parts) in the source data starting at S are not 30 to 39 hex (0 to
9).
ON if the first two digits of the exponential part do not contain 45 and 2B hex (E+) or 45 and 2D hex
(E-). in the source data starting at S are not 30 to 39 hex (0 to 9).
ON if there are two or more exponential parts in the source data.
ON if the data is + or - after conversion.
ON if there are 0 characters in the text data.
ON if a byte containing 00 hex is not found within the first 25 characters.
OFF in all other cases.
Equals Flag P_EQ ON if the conversion result is 0.
OFF in all other cases.
S: First source word
D: First destination word
FVAL(449)
S
D