5 arithmetic/logic unit (alu), Arithmetic/logic unit (alu) – Freescale Semiconductor MC68HC08KH12 User Manual

Page 59

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MC68HC(7)08KH12

Rev. 1.1

Advance Information

Freescale Semiconductor

59

C — Carry/Borrow Flag

The CPU sets the carry/borrow flag when an addition operation
produces a carry out of bit 7 of the accumulator or when a subtraction
operation requires a borrow. Some instructions — such as bit test and
branch, shift, and rotate — also clear or set the carry/borrow flag.

1 = Carry out of bit 7
0 = No carry out of bit 7

6.5 Arithmetic/Logic Unit (ALU)

The ALU performs the arithmetic and logic operations defined by the
instruction set.

Refer to the CPU08 Reference Manual (Freescale document number
CPU08RM/AD) for a description of the instructions and addressing
modes and more detail about CPU architecture.

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