HCS12 Assembly Programming - The HCS12/9S12: An Introduction to Software and Hardware Interfacing - page 76

1 01 1 1 1 0 1 1

C flag

01 1 1 1 0 1 1 1

Accumulator B

Figure 2.14a ■ Operation of the rolb instruction

The result is shown in Figure 2.14b.

Original value New value

[B] = 10111101
C = 1

[B] = 01111011
C = 1

Figure 2.14b ■ Execution result of rolb

▲

Example 2.22
▼ What are the values of accumulator A and the C flag after executing the instruction rora
assuming that the original value of A is $BE and C 5 1?
Solution: The operation of this instruction is illustrated in Figure 2.15a.

1 1 0 1 1 1 1 1 0

0 11011111 accumulator A

C flag

Figure 2.15a ■ Operation of the rora instruction