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2 Instructions
CP1E CPU Unit Instructions Reference Manual(W483)
Data Control Instructions
2
SCL2
Flags
Function
SCL2(486) is used to convert the signed binary data contained in the source word S into signed BCD
data (the BCD data contains the absolute value and the Carry Flag shows the sign) and place the result
in the result word R according to the linear function defined by the slope (∆X, ∆Y) and an offset. The
address of the first word containing ∆X, ∆Y, and the offset is specified for the first parameter word P1.
The sign of the result is indicated by the status of the Carry Flag (ON: negative, OFF: positive).
The following equations are used for the conversion.
The offset and slope can be a positive value, 0, or a negative value. Using a negative slope enables
reverse scaling.
•The result will be rounded to the nearest integer.
•The result in R will be the absolute BCD conversion value and the sign will be indicated by the Carry
Flag. The result can thus be between –9999 and 9999.
•If the result is less than –9999, –9999 will be output as the result. If the result is greater than 9999,
9999 will be output.
Name Label Operation
Error Flag P_ER •ON if the contents of C+1 (∆X) is 0000.
•ON if the contents of C+2 (∆Y) is not BCD.
•OFF in all other cases.
Equals Flag P_EQ •ON if the result is 0.
•OFF in all other cases.
Carry Flag P_CY •ON if the result is negative.
•OFF if the result is zero or positive.
R = ∆Y× [(BCD conversion of S) – (BCD conversion of offset)]
BCD conversion of ∆X
Note The slope of the line is ∆Y/∆X.
P1
P1+1
P1+2
R (signed BCD)
S (signed binary)
Offset
R (signed BCD)
S (signed binary)
Offset
R (signed BCD)
S (signed binary)
Offset of 0000
Offset = 0000 hex
Offset
∆Y
∆X
(Signed binary)
(Signed binary)
(Signed BCD)
Positive Offset Negative Offset
∆Y
∆X
∆Y
∆X
∆Y
∆X