1668 HEIDENHAIN Technical Manual MANUALplus 620
8.15.4 LOAD TWO’S COMPLEMENT (L–)
Syntax: L– (LOAD MINUS)
Operands: B, W, D, K
Action:
Load the two’s complement of the addressed operand, or of a constant, into
the word accumulator. If necessary, the control fills the accumulator with the
correct algebraic sign. The two’s complement allows negative numbers to be
stored, i.e., a number loaded with the L command appears in the accumulator
with an inverted sign. This command can be used only with word processing.
Example:
Negate the content of byte B5 and then add it to the content of byte B6.
Assign the result to byte B8.
Initial state:
Byte B5 = 15 (dec)
Byte B6 = 20 (dec)
Byte B8 = ?
Function STL Accumulator
content
Operand content
Load byte B5 into the
word accumulator, invert
the algebraic sign.
L– B5 –15 +15
Add the contents of the
word accumulator and
byte B6.
+ B6 +5 +20
Assign the gating result to
byte B8.
= B8 +5 +5